(PW) be afraid at the last minute, lose confidence
I was prepared to make a speech, but I got cold feet when I saw how many people were going to hear it.
(free)
pl.n. Slang
Fearfulness or timidity preventing the completion of a course of action.
pl n
Informal loss or lack of courage or confidence
(UsingEnglish)
If you get cold feet about something, you lose the courage to do it.
(dictionary) noun Informal .
a loss or lack of courage or confidence; an onset of uncertainty or fear:
She got cold feet when asked to sing a solo.