Idle head given gin cocktail (7)
I believe the answer is:
loafing
'idle' is the definition.
(I've seen this in another clue)
'head given gin cocktail' is the wordplay.
'head' becomes 'loaf' (slang term for the head).
'given' is a charade indicator (letters next to each other).
'cocktail' indicates an anagram.
'gin' with letters rearranged gives 'ing'.
'loaf'+'ing'='LOAFING'
(Other definitions for loafing that I've seen before include "not working" , "Lazing about" , "Being idle" , "Idling, hanging around" .)