アプセトネデブ gets far more web hits.

@@ -5 +5 @@
-<reb>あぷせとねでぶ</reb>
+<reb>アプセトネデブ</reb>
@@ -8 +8,2 @@
-<reb>アプセトネデブ</reb>
+<reb>あぷせとねでぶ</reb>
+<re_inf>&sk;</re_inf>

Can make it "unclassified" rather than "noun".
Marginal and getting very dated as the old OSI model fades into the history of networking, but I think there are enough contemporary WWW pages mentioning it to make it worth keeping.

@@ -11 +11 @@
-<pos>&n;</pos>
+<pos>&unc;</pos>

I don't think it can be both a mnemonic and a noun unless it also refers to the OSI model itself. I'm not seeing any evidence that it does.
Also, a mnemonic would need to be glossed something like this. I don't think it should be an entry.

@@ -14 +14 @@
-<gloss>OSI 7-layer model mnemonic (application, presentation, session, transport, network, data-link, physical)</gloss>
+<gloss>A-P-S-T-N-D-P (mnemonic for the OSI 7-layer model; application, presentation, session, transport, network, data-link, physical)</gloss>

アプセトネデブ	150
あぷせとねでぶ	225

I hadn't considered it a mnemonic, but it probably is. I'd call it a noun and I think it should be included.

@@ -3,0 +4,3 @@
+<r_ele>
+<reb>あぷせとねでぶ</reb>
+</r_ele>
@@ -8,0 +12 @@
+<xref type="see" seq="2288200">ＯＳＩ</xref>
@@ -10 +14 @@
-<gloss>(acronym for) OSI 7-layer model (application, presentation, session, transport, network, data-link, physical)</gloss>
+<gloss>OSI 7-layer model mnemonic (application, presentation, session, transport, network, data-link, physical)</gloss>

https://e-words.jp/w/アプセトネデブ.html
資格試験のための暗記などで用いられる。
https://ja.wikipedia.org/wiki/OSI参照モデル
OSIモデルを”あぷせとねでぶ”と頭文字を取って学習することがある。

Is this really a noun or is it just a mnemonic? If it's the latter, I'm not sure it's needed as an entry.