Flat cap on tradesman for social gathering? (5)
I believe the answer is:
event
'for social gathering?' is the definition.
(I've seen this in another clue)
'flat cap on tradesman' is the wordplay.
'flat' becomes 'even' (level).
'cap on' indicates taking the first letters (I've seen 'caps on' mean this (the top letters or 'caps')).
The initial letter of 'tradesman' is 't'.
'even'+'t'='EVENT'
(Other definitions for event that I've seen before include "Occurence, happening" , "Something taking place" , "Item in sports programme" , "Affair" , "Something going on" .)