Kitty changed top (3)
I believe the answer is:
pot
'kitty' is the definition.
(both can mean a shared fund)
'changed top' is the wordplay.
'changed' is an anagram indicator.
'top' anagrammed gives 'POT'.
(Other definitions for pot that I've seen before include "Preserve; drug" , "Trophy; kitty" , "Weed" , "Cooking vessel, plant container and street drug" , "Container for 23" .)