Spike's back without leader (3)
I believe the answer is:
ear
'spike's' is the definition.
('ear' can be a synonym of 'spike')
'back without leader' is the wordplay.
'back' becomes 'rear' ('rear' can be a synonym of 'back').
'without leader' means to remove the first letter.
'rear' with its first letter taken off is 'EAR'.
(Other definitions for ear that I've seen before include "Place for a plug" , "Fruiting head of corn" , "Part of cereal plant containing seed" , "Lughole" , "'Give every man thine ..., but few thy voice' (Hamlet)" .)