Spikes (4)
I believe the answer is:
ears
'spikes' is the definition.
('ear' can be a synonym of 'spike')
This is all the clue.
(Other definitions for ears that I've seen before include "Seed-bearing parts of corn" , "Heads of corn" , "Auditors" , "Locations for buds or studs?" , "'''Friends, Romans, countrymen, lend me your ...'' (Julius Caesar) (4)'" .)