Leaving without International medal (4)
I believe the answer is:
gong
'medal' is the definition.
(I've seen this before)
'leaving without international' is the wordplay.
'leaving' becomes 'going' ('going' can be a synonym of 'leaving').
'without' indicates named letters should be taken away.
'international' becomes 'i' (abbreviation eg in IMF).
'going' with 'i' taken out is 'GONG'.
(Other definitions for gong that I've seen before include "Beat this" , "Medal, award or honour (inf)" , "Instrument - award" , "Medal; forty down" , "Percussion instrument - medal (slang)" .)