Strike to involve a corporation (6)
I believe the answer is:
paunch
'corporation' is the definition.
(synonyms)
'strike to involve a' is the wordplay.
'strike' becomes 'punch' (I've seen this before).
'to involve' indicates putting letters inside.
'punch' enclosing 'a' is 'PAUNCH'.
(Other definitions for paunch that I've seen before include "Protuberant stomach" , "Protruding stomach" , "Beer belly" , "Beer-belly" , "Pot" .)