Crush in a party (5)
I believe the answer is:
abash
'crush' is the definition.
(I've seen this before)
'a party' is the wordplay.
'party' becomes 'bash' (bash is a kind of party**).
'a'+'bash'='ABASH'
'in' acts as a link.
(Other definitions for abash that I've seen before include "Rattle" , "Disconcert" , "Strike with embarrassment" , "Discomfit" , "put one to shame" .)