Dictionary of American idioms

VAIN AS A PEACOCK

vain as a peacock: translation

*proud as a peacock&*vain as a peacock
overly proud; vain. (*Also:as\vain as a peacock.) •

Mike's been strutting around proud as a peacock since he won that award.

I sometimes think Elizabeth must spend all day admiring herself in a mirror. She's as vain as a peacock.