* wisdom; chuujiten
* shinmeikai (has 〔古〕 for the armor sense)

Including an explanatory gloss as this is a distinctly Japanese concept that the glosses don't elucidate that 
well, and it's not just used by pregnant women.

@@ -5,0 +6,3 @@
+</k_ele>
+<k_ele>
+<keb>腹巻</keb>
@@ -12 +15,2 @@
-<gloss>breast-protector</gloss>
+<gloss>haramaki</gloss>
+<gloss>bellyband</gloss>
@@ -13,0 +18,6 @@
+<gloss g_type="expl">knit stomach covering (worn for warmth)</gloss>
+</sense>
+<sense>
+<pos>&n;</pos>
+<misc>&hist;</misc>
+<gloss>abdomen armor</gloss>

"Those on foot" may not sound quite as well, might not flow as nicely, but…
"Those on foot" is accurate. "Footsoldiers" is wrong. (footsoldier = common soldier on foot ≠ any and all who fight on foot)
Samurai on foot, e.g., are not footsoldiers. The term "footsoldier" is not, and cannot, be used to refer to them.

"those on foot" instead of "footsoldier"
is horribly bad

Adding the term used in English language sources, as per Robin Scott's quite sensible addition on 胴丸.
Also an extra detail, as it seems weird to have it on 胴丸, but not here.

Also: 胴丸 were called haramaki as well, at first. Haramaki came later, and would then come to be distinguished as haramaki vs doumaru. I dunno if this is too detailed/obscure to add as a further (tagged as obsolete) sense, though.

@@ -23 +23,2 @@
-<gloss>armor put on from the front and fastened in the back</gloss>
+<gloss>armor put on from the front and fastened in the back. Initially made for those on foot, but later came to (along with the dō-maru) replace the heavier and less mobile ō-yoroi on horseback as well</gloss>
+<gloss>haramaki (not to be confused with the stomach covering)</gloss>

Editorial Policy extracts: (https://www.edrdg.org/wiki/index.php/Editorial_policy)
- "provide useful explanations where appropriate. "type of card game" is not very useful - in such a case explain briefly what the card game entails", 
- "do not precede the meaning with the articles "a", "an" or "the" unless it is absolutely necessary to make the meaning clear."
https://military.wikia.org/wiki/Haramaki_(armour) : "Haramaki refers to any Japanese armour which is put on from the front and then fastened in the back with cords. "

As a point of style we try and avoid "type of" glosses.  See if you can come up with a more descriptive gloss.
I am re-inserting some reference material and comments from earlier in this entry, which are now in a fork since later edits started further back in the chain.

…and just "armour" is a bit non-specific, but certainly not wrong.
"armor put on from the front and fastened in the back" is clearer, giving a better idea of the coverage.
Both options also work, whether it's just the cuirass, or the full suit of armour.

>"chest armor" also refers to armor that covers the back.

It can sometimes be used that way …and sometimes not.
I see no reason to use needlessly vague and potentially misleading phrasing. "Torso armour" is a lot clearer, whilst not being longer or more difficult to understand. The term "Cuirass" is even shorter and very clear, though I imagine most people aren't entirely sure of its exact meaning.
…and, of course, if one specifies that that it is a "torso armour"/"cuirass", then the entry needs an additional sense, of a full suit of armour, with such a "cuirass".
(though it also covers further down, as well, I'd say just mentioning the torso is accurate enough, for such a very brief description)

"chest armor" also refers to armor that covers 
the back.

Whilst the English Wikipedia article does say "chest", it also shows examples of the armour, which demonstrate that it also covers the back (though not necessarily completely) and sides, whereas "chest" only refers to the front.
Not to mention how the many other sources I mentioned, also demonstrate and/or explain this, often in greater detail.
Not to mention that it also covers the abdomen and upper thighs.
…and also that haramaki is often, very often, used to refer to the whole suit of armour. (including the helmet, greaves, shoulder protection, gauntlets etc)

Oh, and the fastening method seems a bit of an unnecessary detail, unless we're going to be far more detailed. (and even then, there are a lot of other things that have higher priority. Especially as the use of cords is the standard method, anyway)

@@ -23 +23 @@
-<gloss>chest armor put on from the front and fastened in the back with cords</gloss>
+<gloss>armor put on from the front and fastened in the back</gloss>

https://en.wikipedia.org/wiki/Haramaki_(armour)
"Haramaki is a type of chest armour"
"Haramaki refers to any Japanese armour which is put on from the front and then fastened in the back with cords."

@@ -23 +23 @@
-<gloss>breast protector (armor)</gloss>
+<gloss>chest armor put on from the front and fastened in the back with cords</gloss>

GG5, etc.

@@ -23 +23 @@
-<gloss>A type of armor covering the torso</gloss>
+<gloss>breast protector (armor)</gloss>

Koujien, Daijirin, Daijisen
https://ja.wikipedia.org/wiki/腹巻き
https://ja.wikipedia.org/wiki/腹巻

The "bellybands" were traditionally made of cotton. Woollen ones, have become a thing in more modern times, but cotton ones haven't gone away, by any means. I wouldn't be surprised at further materials as well (why not?), but I didn't bother checking.

The armour is clearly not "abdomen" armour.
It covers the torso. In roughly the same way and with roughly the same coverage, as other old Japanese torso armours. (there are significant differences, of course, but…)
So not only including the back, and not just the abdomen (which is just the front. Just the belly), but also further up to cover the chest (not necessarily all the way up, but that's not unusual for Japanese armour), as well as bits that do down as far as to, at least partially, cover the thighs.
(looked into this when I encountered the, thankfully already removed, definition of "breast-protector" from rikaichan)

@@ -18 +18 @@
-<gloss g_type="expl">knit stomach covering (worn for warmth)</gloss>
+<gloss g_type="expl">stomach covering (worn for warmth)</gloss>
@@ -23 +23 @@
-<gloss>abdomen armor</gloss>
+<gloss>A type of armor covering the torso</gloss>

* wisdom; chuujiten
* shinmeikai (has 〔古〕 for the armor sense)

Including an explanatory gloss as this is a distinctly Japanese concept that the glosses don't elucidate that 
well, and it's not just used by pregnant women.

@@ -5,0 +6,3 @@
+</k_ele>
+<k_ele>
+<keb>腹巻</keb>
@@ -12 +15,2 @@
-<gloss>breast-protector</gloss>
+<gloss>haramaki</gloss>
+<gloss>bellyband</gloss>
@@ -13,0 +18,6 @@
+<gloss g_type="expl">knit stomach covering (worn for warmth)</gloss>
+</sense>
+<sense>
+<pos>&n;</pos>
+<misc>&hist;</misc>
+<gloss>abdomen armor</gloss>

lasted until 1945

@@ -12 +12 @@
-<gloss>Manchukuo (Manchurian prewar Japanese puppet state)</gloss>
+<gloss>Manchukuo (Manchurian pre-defeat Japanese puppet state)</gloss>

大辞林

@@ -13,0 +14 @@
+<gloss>last person (to arrive, finish etc.)</gloss>

@@ -8,0 +9 @@
+<gloss>calculating</gloss>

GG5, ウィズダム和英辞典

"clever" has mostly positive connotations.

@@ -9 +8,0 @@
-<gloss>clever</gloss>
@@ -11,0 +11 @@
+<gloss>unscrupulous</gloss>
@@ -12,0 +13 @@
+<gloss>aggressive</gloss>

Entry created

Changed "designed" to "made".
Better to avoid giving people an idea that the design was changed, when later used on horseback, or that it has features of its design that are better for foot, specifically. It's lighter and more flexible/mobile. Those are benefits, regardless.
The weight and inflexible nature of the ooyoroi was a (much) greater problem on foot, than on horseback, but that is a thing about the ooyoroi, not the doumaru. The doumaru works equally well, on horse and foot.

@@ -16 +16 @@
-<gloss>light armour opening at the right, originally designed for use on foot</gloss>
+<gloss>light armour opening at the right, originally made for use on foot</gloss>

It is no less commonly used to refer to a full suit of armour. You cannot ignore that.
To only state the "torso armour" sense, is to implicitly deny the existence of the "full suit" sense.

That the kokugos fail to recognize this, is one of the ways in which their entry is clearly wrong. As I've noted, they also claim that it was only used on foot, which is clearly false.
This is hardly the only example of kokugos getting things objectively and undeniably wrong.
(just as there are some examples of clear and undeniable errors, in many a en-en dictionary, as well. Not to mention jp-en/en-jp dictionaries, which have a large, shocking, amount of errors that are beyond obvious and quite extremely wrong. My go-to example being that practically all en-jp dictionaries translate "hip" as "尻". IIRC there is one, just one, rather minor, en-jp dictionary that doesn't)

@@ -16 +16 @@
-<gloss>light torso armour opening at the right, originally designed for foot soldiers</gloss>
+<gloss>light armour opening at the right, originally designed for use on foot</gloss>

The fact that 胴丸 came to be used by other types of soldiers does not change the fact that it was designed for footsoldiers. We can add "originally" to be more precise.
"Torso armour" is a crucial detail. 胴 is in the name. I don't think it's necessary to mention that 胴丸 can also refer to the complete suit of armour. The kokugos don't either.

@@ -16 +16 @@
-<gloss>light armour opening at the right</gloss>
+<gloss>light torso armour opening at the right, originally designed for foot soldiers</gloss>

I have extensively explained why having a single sense calling it a torso armour, is wrong
…as well as why claiming that it is for footsoldiers, is wrong in multiple ways.

@@ -16 +16 @@
-<gloss>light torso armour opening at the right (designed for foot soldiers)</gloss>
+<gloss>light armour opening at the right</gloss>

I'll merge the competing versions and close it.

@@ -16 +16 @@
-<gloss>armour that opens at the right</gloss>
+<gloss>light torso armour opening at the right (designed for foot soldiers)</gloss>

I.e. reverting to a version that gives a false definition.
Okay, so it needs to be short…
Seems my impression of how brief the definitions need to be, wasn't really all that off…

@@ -16 +16 @@
-<gloss>light torso armour designed for foot soldiers</gloss>
+<gloss>armour that opens at the right</gloss>

For a term like this a short explanation is best. People can go off to other sources if 
they want more. I'm reverting to Robin's previous version.

@@ -16 +16 @@
-<gloss>light armour initially used on foot, but later also from horseback. Opens on the right side</gloss>
+<gloss>light torso armour designed for foot soldiers</gloss>

@@ -16 +16 @@
-<gloss>light armour that opens on the right side. Initially used on foot, but later also from horseback</gloss>
+<gloss>light armour initially used on foot, but later also from horseback. Opens on the right side</gloss>

Nothing that contradicts the kokugos?
How about:
jwiki:
"しかし、その後の戦法の変化に伴い、胴丸はしだいに騎乗の上級武士にも用いられるようになり、デザイン的にも上級武士に相応しい華美なものへと発展していく。南北朝時代頃からは、胴丸の武士も兜・大袖を着用することが一般的になった。"
myarmoury:
"During the Mongolian invasions (1274 and 1281) and especially in the next century, the role of the infantry on the battlefield increased dramatically. Many of the poorer and low-ranking samurai preferred to fight on foot. Although the heavy, box-like o-yoroi was modernized to some degree in the 13th century, it remained quite unsuitable for infantry combat. At the same time, the do-maru's comfort, ease in wear and use on the battlefield made it a favoured replacement for the o-yoroi and other types of armour in such combat."
https://www.nihonto.com/a-brief-history-of-japanese-armor/
"The dômaru and haramaki were the first light body armor for infantry.  During the Muromachi era, they came to be used with helmets and shoulder guards in the place of ô-yoroi by military commanders."

I still question the notion of calling it light, but as some sources do refer to it as such, I'll let it slide.
(BTW, anything said of the doumaru, is also true of the haramaki. The only difference being, that the doumaru opens at the right side, and the haramaki at the back. As the ooyoroi died out, it was not quite replaced by the doumaru, but rather by the doumaru and the haramaki)

…and, again, suits of armour including a doumaru "cuirass", are also typically (always?) referred to as doumaru. Hence you cannot specify it as "chest armour", unless you also add an extra sense, of a suit of armour with such a chest armour.

@@ -16 +16 @@
-<gloss>light torso armour designed for foot soldiers</gloss>
+<gloss>light armour that opens on the right side. Initially used on foot, but later also from horseback</gloss>

jwiki: "胴丸（どうまる）は、日本の鎧の形式の1つ。平安時代中期頃生じたもので、徒歩戦に適した鎧の形式である。 "
http://myarmoury.com/feature_jpn_armour.html
"At the beginning of this period retainers and servants usually wore simpler armour (do-maru) [...] The warriors who wore do-maru usually walked or ran near the horse of their lord."

That gloss is far too long. I'm not seeing anything in the sources provided that contradicts the kokugo definitions. I think we should drop the mention of samurai altogether to avoid confusion.

@@ -16 +16 @@
-<gloss>torso armour that opens at the right side. Initially made for those on foot, but later came to (along with the haramaki) replace the heavier and less mobile ō-yoroi on horseback as well</gloss>
+<gloss>light torso armour designed for foot soldiers</gloss>
@@ -18,5 +17,0 @@
-</sense>
-<sense>
-<pos>&n;</pos>
-<misc>&hist;</misc>
-<gloss>suit or armour, with such a torso armour</gloss>

@@ -16 +16 @@
-<gloss>torso armour that opens at the right side. Initially made for those on foot, but later came to replace the heavier and less mobile ō-yoroi on horseback as well</gloss>
+<gloss>torso armour that opens at the right side. Initially made for those on foot, but later came to (along with the haramaki) replace the heavier and less mobile ō-yoroi on horseback as well</gloss>

Ah, so the policy is like that? That's more to my liking, actually.
I made it so simple and brief, due to my (apparently a bit mistaken) impression of how JMdict is.
Okay, a bit more explanatory, then.

Not sure if it's best to says "torso armour", and then add a second sense, or if it's better to just say "armour", but…

>All the kokugos describe it as light/comfortable/simple armour designed for foot soldiers.

…and all the other sources I mention, make it clear that the kokugos are wrong.
Certainly, this isn't an encyclopedia and it needs to be shorter. This does not excuse making it clearly wrong, however, nor does it mean that the kokugos are, or possibly could be, more reliable than the other sources I mentioned, in terms of what a doumaru is.

BTW, I find it very weird, that English language sources like add a hyphen, in the name. (this is merely a comment on the practice)

@@ -16 +16 @@
-<gloss>light torso armour designed for foot soldiers and later worn by samurai</gloss>
+<gloss>torso armour that opens at the right side. Initially made for those on foot, but later came to replace the heavier and less mobile ō-yoroi on horseback as well</gloss>
@@ -17,0 +18,5 @@
+</sense>
+<sense>
+<pos>&n;</pos>
+<misc>&hist;</misc>
+<gloss>suit or armour, with such a torso armour</gloss>

Editorial Policy extracts: (https://www.edrdg.org/wiki/index.php/Editorial_policy)
- "provide useful explanations where appropriate. "type of card game" is not very useful - in such a case explain briefly what the card game entails",

daijr/s, koj, nikk, shinmeikai

All the kokugos describe it as light/comfortable/simple armour designed for foot soldiers. This isn't an encyclopedia so we can't mention everything but we need to include the key details.
"Dō-maru" is common in English-language sources so I've added it as a gloss.
Please do not delete the exiting gloss unless you wish to improve upon it. "A type of armour" is not a helpful translation.

@@ -16 +16,2 @@
-<gloss>type of armour</gloss>
+<gloss>light torso armour designed for foot soldiers and later worn by samurai</gloss>
+<gloss>dō-maru</gloss>

What's the basis for the description as "light"? It is lighter than the ooyoroi, certainly, but that says more about the ooyoroi. (which was, as I've explained, later replaced by the doumaru, with no one using the relatively heavy and inflexible oyoroi, anymore. Though, to be fair to the oyoroi, it was used for several centuries)

As for "chest armour":
As per the 丸, it wraps around the torso/胴 (with, as previously mentioned, an opening at the right side), thus covering the sides and back as well …and has bits that drape down all the way to the thighs.

So it doesn't just cover the chest, but also the sides and back, as well as abdomen and upper thighs. The term "cuirass" does at least mean an armour that covers both the front and back of the chest-area (but not the things that drape down, to protect further down), and is hence decently okay as a description/translation, but "chest armour" is far too inaccurate and misleading.

Also, "used primarily by foot soldiers and later by samurai" is quite wrong, on two counts.
"primarily by" is wrong, unless ones adds a "at first" or "initially" before it
…and, as I said, footsoldiers implies (outright means?) common soldiers, but some samurai also fought on foot. Though as the sentence later states "…and later by samurai", it's far more than an implication.

@@ -16 +16 @@
-<gloss>light chest armour used primarily by foot soldiers and later by samurai</gloss>
+<gloss>type of armour</gloss>

Looks good to me.

daijr

I'd go with this.

@@ -16,6 +16 @@
-<gloss>A type of Japanese cuirass.</gloss>
-</sense>
-<sense>
-<pos>&n;</pos>
-<misc>&hist;</misc>
-<gloss>suit of armour, with such a cuirass</gloss>
+<gloss>light chest armour used primarily by foot soldiers and later by samurai</gloss>

http://myarmoury.com/feature_jpn_armour.html (though it doesn't explicitly state that it was used on horseback)
https://ja.wikipedia.org/wiki/胴丸
https://www.nihonto.com/a-brief-history-of-japanese-armor/

Whilst doumaru were, initially, used by retainers/ashigaru, they were later used by samurai, as well.
Initially poorer samurai and/or ones that fought on foot, but was later also used by rich and/or horse-riding samurai as well, replacing the ooyoroi (which they had used before)

What is sometimes called a cuirass, does also include what one might call faulds, which drape down over the lower parts, all the way down to the thighs. Hence "cuirass" is not an entirely accurate description …but it's close enough, I suppose.

@@ -16 +16,6 @@
-<gloss>simple cuirass worn by footsoldiers</gloss>
+<gloss>A type of Japanese cuirass.</gloss>
+</sense>
+<sense>
+<pos>&n;</pos>
+<misc>&hist;</misc>
+<gloss>suit of armour, with such a cuirass</gloss>

Daijisen

@@ -15 +15,2 @@
-<gloss>A type of Japanese armour.</gloss>
+<misc>&hist;</misc>
+<gloss>simple cuirass worn by footsoldiers</gloss>

"Medieval" refers to a European time period. It is sometimes used for a somewhat analogous period in Japanese history, but… such use either needs clarification, or clear context. (one might argue that the latter is true, here, but… I wouldn't fully agree)
Also, "lacking a solid breastplate and sleeves" is not a distinguishing feature of the doumaru, as that is true of almost all Japanese armours.

Either this needs a far more thorough description, that refers to it's actual distinguishing features (that it wraps around the person, with an opening at the right side, being the most notable) …or just note that it's a Japanese armour, and let people look it up in an encyclopedia and/or a more armour/militaria dedicated resource.

@@ -15 +15 @@
-<gloss>medieval armour lacking a solid breastplate and sleeves</gloss>
+<gloss>A type of Japanese armour.</gloss>

wiki

@@ -15,1 +15,1 @@
-<gloss>medieval armor</gloss>
+<gloss>medieval armour lacking a solid breastplate and sleeves</gloss>

koj

"I don't think" isn't and argument or clarification.
You say it isn't an improvement, but don't explain how or why it isn't.
Also, "infantry" is pretty much the same as "foot soldier", including the same problems.

As for "torso armour"… Yes, certainly, it is clearer, though I'd argue that if the term "armour" is used, without mention of what part your talking about, people will tend to assume that it is either torso armour, or a full suit of armour, which would be fine, here.
But okay.
"Torso armour" it is
…but then it needs to explicitly state the second sense.
(this makes this entry, inconsistent with the other armour entries, BTW)

@@ -16 +16,7 @@
-<gloss>light torso armour opening at the right, originally designed for infantry combat</gloss>
+<gloss>light torso armour opening at the right, originally used for combat on foot</gloss>
+<gloss>dō-maru</gloss>
+</sense>
+<sense>
+<pos>&n;</pos>
+<misc>&hist;</misc>
+<gloss>suit of armour, using such a torso armour</gloss>

I don't think those changes improve the gloss.
I'm not yielding on the "torso" point. Dropping it makes the gloss less precise and harder to visualise.

@@ -16 +16 @@
-<gloss>light armour opening at the right, originally made for use on foot</gloss>
+<gloss>light torso armour opening at the right, originally designed for infantry combat</gloss>

Changed "designed" to "made".
Better to avoid giving people an idea that the design was changed, when later used on horseback, or that it has features of its design that are better for foot, specifically. It's lighter and more flexible/mobile. Those are benefits, regardless.
The weight and inflexible nature of the ooyoroi was a (much) greater problem on foot, than on horseback, but that is a thing about the ooyoroi, not the doumaru. The doumaru works equally well, on horse and foot.

@@ -16 +16 @@
-<gloss>light armour opening at the right, originally designed for use on foot</gloss>
+<gloss>light armour opening at the right, originally made for use on foot</gloss>

It is no less commonly used to refer to a full suit of armour. You cannot ignore that.
To only state the "torso armour" sense, is to implicitly deny the existence of the "full suit" sense.

That the kokugos fail to recognize this, is one of the ways in which their entry is clearly wrong. As I've noted, they also claim that it was only used on foot, which is clearly false.
This is hardly the only example of kokugos getting things objectively and undeniably wrong.
(just as there are some examples of clear and undeniable errors, in many a en-en dictionary, as well. Not to mention jp-en/en-jp dictionaries, which have a large, shocking, amount of errors that are beyond obvious and quite extremely wrong. My go-to example being that practically all en-jp dictionaries translate "hip" as "尻". IIRC there is one, just one, rather minor, en-jp dictionary that doesn't)

@@ -16 +16 @@
-<gloss>light torso armour opening at the right, originally designed for foot soldiers</gloss>
+<gloss>light armour opening at the right, originally designed for use on foot</gloss>

The fact that 胴丸 came to be used by other types of soldiers does not change the fact that it was designed for footsoldiers. We can add "originally" to be more precise.
"Torso armour" is a crucial detail. 胴 is in the name. I don't think it's necessary to mention that 胴丸 can also refer to the complete suit of armour. The kokugos don't either.

@@ -16 +16 @@
-<gloss>light armour opening at the right</gloss>
+<gloss>light torso armour opening at the right, originally designed for foot soldiers</gloss>

I have extensively explained why having a single sense calling it a torso armour, is wrong
…as well as why claiming that it is for footsoldiers, is wrong in multiple ways.

@@ -16 +16 @@
-<gloss>light torso armour opening at the right (designed for foot soldiers)</gloss>
+<gloss>light armour opening at the right</gloss>

I'll merge the competing versions and close it.

@@ -16 +16 @@
-<gloss>armour that opens at the right</gloss>
+<gloss>light torso armour opening at the right (designed for foot soldiers)</gloss>

I.e. reverting to a version that gives a false definition.
Okay, so it needs to be short…
Seems my impression of how brief the definitions need to be, wasn't really all that off…

@@ -16 +16 @@
-<gloss>light torso armour designed for foot soldiers</gloss>
+<gloss>armour that opens at the right</gloss>

For a term like this a short explanation is best. People can go off to other sources if 
they want more. I'm reverting to Robin's previous version.

@@ -16 +16 @@
-<gloss>light armour initially used on foot, but later also from horseback. Opens on the right side</gloss>
+<gloss>light torso armour designed for foot soldiers</gloss>

@@ -16 +16 @@
-<gloss>light armour that opens on the right side. Initially used on foot, but later also from horseback</gloss>
+<gloss>light armour initially used on foot, but later also from horseback. Opens on the right side</gloss>

Nothing that contradicts the kokugos?
How about:
jwiki:
"しかし、その後の戦法の変化に伴い、胴丸はしだいに騎乗の上級武士にも用いられるようになり、デザイン的にも上級武士に相応しい華美なものへと発展していく。南北朝時代頃からは、胴丸の武士も兜・大袖を着用することが一般的になった。"
myarmoury:
"During the Mongolian invasions (1274 and 1281) and especially in the next century, the role of the infantry on the battlefield increased dramatically. Many of the poorer and low-ranking samurai preferred to fight on foot. Although the heavy, box-like o-yoroi was modernized to some degree in the 13th century, it remained quite unsuitable for infantry combat. At the same time, the do-maru's comfort, ease in wear and use on the battlefield made it a favoured replacement for the o-yoroi and other types of armour in such combat."
https://www.nihonto.com/a-brief-history-of-japanese-armor/
"The dômaru and haramaki were the first light body armor for infantry.  During the Muromachi era, they came to be used with helmets and shoulder guards in the place of ô-yoroi by military commanders."

I still question the notion of calling it light, but as some sources do refer to it as such, I'll let it slide.
(BTW, anything said of the doumaru, is also true of the haramaki. The only difference being, that the doumaru opens at the right side, and the haramaki at the back. As the ooyoroi died out, it was not quite replaced by the doumaru, but rather by the doumaru and the haramaki)

…and, again, suits of armour including a doumaru "cuirass", are also typically (always?) referred to as doumaru. Hence you cannot specify it as "chest armour", unless you also add an extra sense, of a suit of armour with such a chest armour.

@@ -16 +16 @@
-<gloss>light torso armour designed for foot soldiers</gloss>
+<gloss>light armour that opens on the right side. Initially used on foot, but later also from horseback</gloss>

jwiki: "胴丸（どうまる）は、日本の鎧の形式の1つ。平安時代中期頃生じたもので、徒歩戦に適した鎧の形式である。 "
http://myarmoury.com/feature_jpn_armour.html
"At the beginning of this period retainers and servants usually wore simpler armour (do-maru) [...] The warriors who wore do-maru usually walked or ran near the horse of their lord."

That gloss is far too long. I'm not seeing anything in the sources provided that contradicts the kokugo definitions. I think we should drop the mention of samurai altogether to avoid confusion.

@@ -16 +16 @@
-<gloss>torso armour that opens at the right side. Initially made for those on foot, but later came to (along with the haramaki) replace the heavier and less mobile ō-yoroi on horseback as well</gloss>
+<gloss>light torso armour designed for foot soldiers</gloss>
@@ -18,5 +17,0 @@
-</sense>
-<sense>
-<pos>&n;</pos>
-<misc>&hist;</misc>
-<gloss>suit or armour, with such a torso armour</gloss>

@@ -16 +16 @@
-<gloss>torso armour that opens at the right side. Initially made for those on foot, but later came to replace the heavier and less mobile ō-yoroi on horseback as well</gloss>
+<gloss>torso armour that opens at the right side. Initially made for those on foot, but later came to (along with the haramaki) replace the heavier and less mobile ō-yoroi on horseback as well</gloss>

Ah, so the policy is like that? That's more to my liking, actually.
I made it so simple and brief, due to my (apparently a bit mistaken) impression of how JMdict is.
Okay, a bit more explanatory, then.

Not sure if it's best to says "torso armour", and then add a second sense, or if it's better to just say "armour", but…

>All the kokugos describe it as light/comfortable/simple armour designed for foot soldiers.

…and all the other sources I mention, make it clear that the kokugos are wrong.
Certainly, this isn't an encyclopedia and it needs to be shorter. This does not excuse making it clearly wrong, however, nor does it mean that the kokugos are, or possibly could be, more reliable than the other sources I mentioned, in terms of what a doumaru is.

BTW, I find it very weird, that English language sources like add a hyphen, in the name. (this is merely a comment on the practice)

@@ -16 +16 @@
-<gloss>light torso armour designed for foot soldiers and later worn by samurai</gloss>
+<gloss>torso armour that opens at the right side. Initially made for those on foot, but later came to replace the heavier and less mobile ō-yoroi on horseback as well</gloss>
@@ -17,0 +18,5 @@
+</sense>
+<sense>
+<pos>&n;</pos>
+<misc>&hist;</misc>
+<gloss>suit or armour, with such a torso armour</gloss>

Editorial Policy extracts: (https://www.edrdg.org/wiki/index.php/Editorial_policy)
- "provide useful explanations where appropriate. "type of card game" is not very useful - in such a case explain briefly what the card game entails",

daijr/s, koj, nikk, shinmeikai

All the kokugos describe it as light/comfortable/simple armour designed for foot soldiers. This isn't an encyclopedia so we can't mention everything but we need to include the key details.
"Dō-maru" is common in English-language sources so I've added it as a gloss.
Please do not delete the exiting gloss unless you wish to improve upon it. "A type of armour" is not a helpful translation.

@@ -16 +16,2 @@
-<gloss>type of armour</gloss>
+<gloss>light torso armour designed for foot soldiers and later worn by samurai</gloss>
+<gloss>dō-maru</gloss>

What's the basis for the description as "light"? It is lighter than the ooyoroi, certainly, but that says more about the ooyoroi. (which was, as I've explained, later replaced by the doumaru, with no one using the relatively heavy and inflexible oyoroi, anymore. Though, to be fair to the oyoroi, it was used for several centuries)

As for "chest armour":
As per the 丸, it wraps around the torso/胴 (with, as previously mentioned, an opening at the right side), thus covering the sides and back as well …and has bits that drape down all the way to the thighs.

So it doesn't just cover the chest, but also the sides and back, as well as abdomen and upper thighs. The term "cuirass" does at least mean an armour that covers both the front and back of the chest-area (but not the things that drape down, to protect further down), and is hence decently okay as a description/translation, but "chest armour" is far too inaccurate and misleading.

Also, "used primarily by foot soldiers and later by samurai" is quite wrong, on two counts.
"primarily by" is wrong, unless ones adds a "at first" or "initially" before it
…and, as I said, footsoldiers implies (outright means?) common soldiers, but some samurai also fought on foot. Though as the sentence later states "…and later by samurai", it's far more than an implication.

@@ -16 +16 @@
-<gloss>light chest armour used primarily by foot soldiers and later by samurai</gloss>
+<gloss>type of armour</gloss>

Looks good to me.

daijr

I'd go with this.

@@ -16,6 +16 @@
-<gloss>A type of Japanese cuirass.</gloss>
-</sense>
-<sense>
-<pos>&n;</pos>
-<misc>&hist;</misc>
-<gloss>suit of armour, with such a cuirass</gloss>
+<gloss>light chest armour used primarily by foot soldiers and later by samurai</gloss>

http://myarmoury.com/feature_jpn_armour.html (though it doesn't explicitly state that it was used on horseback)
https://ja.wikipedia.org/wiki/胴丸
https://www.nihonto.com/a-brief-history-of-japanese-armor/

Whilst doumaru were, initially, used by retainers/ashigaru, they were later used by samurai, as well.
Initially poorer samurai and/or ones that fought on foot, but was later also used by rich and/or horse-riding samurai as well, replacing the ooyoroi (which they had used before)

What is sometimes called a cuirass, does also include what one might call faulds, which drape down over the lower parts, all the way down to the thighs. Hence "cuirass" is not an entirely accurate description …but it's close enough, I suppose.

@@ -16 +16,6 @@
-<gloss>simple cuirass worn by footsoldiers</gloss>
+<gloss>A type of Japanese cuirass.</gloss>
+</sense>
+<sense>
+<pos>&n;</pos>
+<misc>&hist;</misc>
+<gloss>suit of armour, with such a cuirass</gloss>

Daijisen

@@ -15 +15,2 @@
-<gloss>A type of Japanese armour.</gloss>
+<misc>&hist;</misc>
+<gloss>simple cuirass worn by footsoldiers</gloss>

"Medieval" refers to a European time period. It is sometimes used for a somewhat analogous period in Japanese history, but… such use either needs clarification, or clear context. (one might argue that the latter is true, here, but… I wouldn't fully agree)
Also, "lacking a solid breastplate and sleeves" is not a distinguishing feature of the doumaru, as that is true of almost all Japanese armours.

Either this needs a far more thorough description, that refers to it's actual distinguishing features (that it wraps around the person, with an opening at the right side, being the most notable) …or just note that it's a Japanese armour, and let people look it up in an encyclopedia and/or a more armour/militaria dedicated resource.

@@ -15 +15 @@
-<gloss>medieval armour lacking a solid breastplate and sleeves</gloss>
+<gloss>A type of Japanese armour.</gloss>

wiki

@@ -15,1 +15,1 @@
-<gloss>medieval armor</gloss>
+<gloss>medieval armour lacking a solid breastplate and sleeves</gloss>

koj

Given the newly expanded 決まる entry, I think it would be better to change this to に決まっている and drop senses 1 and 3.
These aren't the only senses of 決まる that can be used in the 〜ている form. We're even missing the most common "to be decided" one.

@@ -35 +35 @@
-<xref type="see" seq="1591420">決まる・きまる・2</xref>
+<xref type="see" seq="1591420">決まる・4</xref>

Good point. I think that covers it better. I'll propose adding キマる to the 決まる entry and drop this one.

@@ -13,4 +12,0 @@
-</r_ele>
-<r_ele>
-<reb>キマっている</reb>
-<re_nokanji/>

決まる	2216938
キマる	44336

I'm not sure it's needed either. The hits for キマっている are 0.2% of those for 決まっている. We don't have キマる, which is far more common.

I saw it used in a couple of places.

Is it really? You can probably get
more hits for タベる

決まっている	1206145
決っている	8134
キマっている	2641

Worth mentioning.

@@ -12,0 +13,4 @@
+</r_ele>
+<r_ele>
+<reb>キマっている</reb>
+<re_nokanji/>

gg5 example: "薬はまずいに決まっている"

Sense 2 is always に決まっている but not necessarily after a verb.

@@ -26,2 +26,3 @@
-<s_inf>usu. as Vに決まっている</s_inf>
-<gloss>ought to ...</gloss>
+<s_inf>as 〜に決まっている</s_inf>
+<gloss>sure to ...</gloss>
+<gloss>certain to ...</gloss>
@@ -29,2 +30 @@
-<gloss>doomed to ...</gloss>
-<gloss>sure to ...</gloss>
+<gloss>it's natural that ...</gloss>

shinmeikai; 8134 ngrams

@@ -5,0 +6,4 @@
+</k_ele>
+<k_ele>
+<keb>決っている</keb>
+<ke_inf>&io;</ke_inf>

GG5 (決まっている entry), 中辞典 (決まる entry example)
に決まっている	253660
決まっている	1206145
10 Tanaka sentences for 決まっている, of which 7 are に決まっている
GG5 has heaps of 決まっている examples.

I think this is more useful.

@@ -5 +5 @@
-<keb>に決まっている</keb>
+<keb>決まっている</keb>
@@ -8 +8 @@
-<reb>にきまっている</reb>
+<reb>きまっている</reb>
@@ -12,2 +12,22 @@
-<gloss>it goes without saying</gloss>
-<gloss>it's natural that...</gloss>
+<pos>&v1;</pos>
+<xref type="see" seq="1591420">決まる・きまる・1</xref>
+<gloss>to be fixed</gloss>
+<gloss>to be determined</gloss>
+<gloss>to be common</gloss>
+<gloss>to be destined</gloss>
+</sense>
+<sense>
+<pos>&exp;</pos>
+<pos>&v1;</pos>
+<s_inf>usu. as Vに決まっている</s_inf>
+<gloss>ought to ...</gloss>
+<gloss>bound to ...</gloss>
+<gloss>doomed to ...</gloss>
+<gloss>sure to ...</gloss>
+</sense>
+<sense>
+<pos>&exp;</pos>
+<pos>&v1;</pos>
+<xref type="see" seq="1591420">決まる・きまる・2</xref>
+<gloss>to look good (on)</gloss>
+<gloss>to be stylish</gloss>

EDR https://eow.alc.co.jp/search?q=に決まっている

Prompted by seeing these two sentences in the wild: 昔のことなんてよく覚えてないに決まってんだろ。and 何言ってんの。そんなの冗談にきまってんじゃない。

変異種	8886

https://news.yahoo.co.jp/pickup/6376179
"デンマークで毛皮用に飼育されているミンクから新型コロナウイルスの変異種が見つかった問題で..."
https://www.bbc.com/news/science-environment-54867653
"The mink were culled and the mutated strain did not infect humans..."
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https://context.reverso.net/translation/japanese-english/変異種