Clergyman that might deliver broadside, did you say? (5)
I believe the answer is:
canon
'clergyman' is the definition.
(canon is a kind of clergyman)
'that might deliver broadside did you say?' is the wordplay.
'that might deliver broadside' becomes 'cannon' (broadside can mean shots from cannon).
'did you say?' indicates a 'sounds like' (homophone) clue.
'cannon' is a homophone of 'CANON'.
(Other definitions for canon that I've seen before include "Body of established rules or principles" , "Big type" , "General rule; cleric" , "General rule; clergyman" , "Principle; list of recognised works" .)