French friend to leave Spanish friend (5)
I believe the answer is:
amigo
'spanish friend' is the definition.
(I've seen this in another clue)
'french friend to leave' is the wordplay.
'french friend' becomes 'ami' (I've seen this before).
'to leave' becomes 'go' (to go is to depart or leave).
'ami'+'go'='AMIGO'
(Other definitions for amigo that I've seen before include "Mexican friend" , "Mate in Madrid?" , "Mexican's mate" , "friend in Uruguay" , "friend from Barcelona" .)