Departing, I must leave to find medal (4)
I believe the answer is:
'medal' is the definition.
(informal term for a medal or prize)
'departing i must leave' is the wordplay.
'departing' becomes 'going' ('go' can be a synonym of 'depart').
'must leave' suggests deleting specific letters.
'going' with 'i' taken out is 'GONG'.
'to find' is the link.
(Other definitions for gong that I've seen before include "Medal, award or honour (inf)" , "Dinner call - medal" , "Dinner bell or slangy medal" , "Dinner instrument?" , "Round metal plate struck to resound" .)