Clergyman, for short (3)
I believe the answer is:
rev
'clergyman for short' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for rev that I've seen before include "serviceman?" , "Clergyman, or woman (abbr)" , "Gun (an engine)" , "One turn of an engine, in short" , "Cleric" .)