Boast about tiff (4)
I believe the answer is:
crow
'boast' is the definition.
(crow is a kind of boast)
'about tiff' is the wordplay.
'about' becomes 'c' (abbreviation for 'circa'**).
'tiff' becomes 'row'.
'c'+'row'='CROW'
(Other definitions for crow that I've seen before include "Make sounds of pleasure as a baby does - or a bird" , "Common bird" , "Black bird; boast" , "Native American -- bird" , "Gloat" .)