Best Pride party? (5)
I believe the answer is:
outdo
'best' is the definition.
(I know that best can be written as outdo)
'pride party?' is the wordplay.
'pride' becomes 'out' (I am not sure about this - if you are sure you should believe this answer much more).
'party?' becomes 'do' (do is a kind of party).
'out'+'do'='OUTDO'
(Other definitions for outdo that I've seen before include "Exceed" , "Defeat" , "Best" , "Overtake" , "Get the better of" .)