Is overproud (6)
I believe the answer is:
boasts
'is overproud' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for boasts that I've seen before include "Blows one's own trumpet" , "Brags in praise of oneself" , "crows" , "Brags, shows off" , "Brags, blows" .)