Spike article in case of entrepreneur (3)
I believe the answer is:
ear
'spike' is the definition.
('ear' can be a synonym of 'spike')
'article in case of entrepreneur' is the wordplay.
'article' becomes 'a' (indefinite article).
'in' is an insertion indicator.
'case of' suggests removing the centre (outsides of).
'entrepreneur' with its centre taken out is 'er'.
'a' put within 'er' is 'EAR'.
(Other definitions for ear that I've seen before include "Listening organ" , "See 8" , "Shell-like; corn" , "A corny bit" , "Part of a cereal plant containing the seeds" .)