Play being about fashion, time to bury old hat! (3,7,4)
I believe the answer is:
the winters tale
'play' is the definition.
(I've seen this before)
'about fashion time to bury old hat' is the wordplay.
'about' is an insertion indicator.
'fashion' becomes 'hew' (both can mean to work or carve into shape).
'time' becomes 't' (abbreviation).
'to bury' becomes 'inter' ('inter' can be a synonym of 'bury').
'old hat' becomes 'stale' (both can mean out of date).
't'+'inter'='tinter'
'hew' placed inside 'tinter' is 'thewinter'.
'thewinter'+'stale'='THE WINTERS TALE'
'being' acts as a link.
(Other definitions for the winters tale that I've seen before include "Play" , "The Bard's work" , "entertainment" .)