G n-grams: 
ビビる	166047
びびる	84771
GG5, etc. (the JEs don't attempt to split out senses.)

Good edit, IMO.

Daijr, Daijs
http://www.weblio.jp/content/びびる
http://gogen-allguide.com/hi/bibiru.html

There was no clear difference between the original two senses so I decided to have a go at redoing this entry.
-
None of the Japanese sources I checked make much of a distinction between "fear", "nervousness", and "surprise" despite being (in my opinion) quite different different feelings (albeit with some overlap).
After reading dozens of sentences, I've come up with two senses that I believe cover the contemporary uses of this word. 
-
The first sense encompasses the feelings of "fear" and "nervousness" in a way that satisfies the "気後れする" and "おじけづく/気持ちが萎縮する" definitions listed in Daijr and Daijs respectively. Some example sentences:
-
1. 大舞台でびびってしまう
2. ここでびびっては負けだ、強気でいけ
3. 言おうと意識していてもびびっちゃって言えない
-
The feelings covered by the second sense all include an element of surprise. Another difference with this sense is that the feeling isn't necessarily negative (as shown by examples 6 and 10).
-
4. いきなり携帯が鳴りだしてビビったわ！
5. 一瞬幽霊かと思ってビビった
6. とても美味しくてびびった
7. 突然Outlook.comからアカウント利用停止メールが来てビビった
8. 初めて東京を訪れてビビった場所ランキング
9. 今でも変わってなくてビビった校則
10. iMovie初めて使ったけど使いやすくてびびった
-
I've tagged the second sense as "colloquial" but a case could be made that that's not always the case. According to Daijr, even the first sense is colloquial but I have trouble accepting that given that びびる has been used in that way since the Heian period (see 3rd ref.).
-
The third sense comes from Daijr and AFAIK is no longer used.
-
There's some original research here so feel free to disagree/make further changes.
-
Finally, I don't have n-gram data but a Google search tells me that the katakana representation of this word is more common.

@@ -3,0 +4,3 @@
+<r_ele>
+<reb>ビビる</reb>
+</r_ele>
@@ -10,0 +14 @@
+<gloss>to feel afraid</gloss>
@@ -12 +16,3 @@
-<gloss>to feel surprise</gloss>
+<gloss>to lose one's nerve</gloss>
+<gloss>to get cold feet</gloss>
+<gloss>to get the jitters</gloss>
@@ -18,2 +24,3 @@
-<gloss>to get cold feet</gloss>
-<gloss>to get the jitters</gloss>
+<gloss>to be startled</gloss>
+<gloss>to be surprised</gloss>
+<gloss>to be shocked</gloss>
@@ -20,0 +28,8 @@
+<gloss>to be spooked</gloss>
+</sense>
+<sense>
+<pos>&v5r;</pos>
+<pos>&vi;</pos>
+<misc>&arch;</misc>
+<gloss>to be shy</gloss>
+<gloss>to be bashful</gloss>

Entry created