Leave European team ahead of time (4)
I believe the answer is:
exit
'leave' is the definition.
(I know that leave can be written as exit)
'european team ahead of time' is the wordplay.
'european' becomes 'e' (abbreviation e.g. EU).
'team' becomes 'XI' (a football team, from Roman numerals for 11).
'ahead of' is a charade indicator (letters next to each other) (some letters go in front of others).
'time' becomes 't' (abbreviation).
'e'+'xi'+'t'='EXIT'
(Other definitions for exit that I've seen before include "Depart" , "Outlet" , "Actor's departure" , "Leave the stage" , "Player's departure" .)