Gong bringing first of diners into dinner, perhaps (5)
I believe the answer is:
medal
'gong' is the definition.
(I've seen this before)
'first of diners into dinner perhaps' is the wordplay.
'first of' says to take the initial letters.
'into' is an insertion indicator.
'dinner perhaps' becomes 'meal' (dinner is a kind of meal).
The first letter of 'diners' is 'd'.
'd' put inside 'meal' is 'MEDAL'.
'bringing' acts as a link.
(Other definitions for medal that I've seen before include "An award, in slang a gong" , "Lamed by award" , "Award for distinction" , "Metal disc awarded as prize, say in Olympics" , "Winner's award" .)