On protective coat receive mark (6)
I believe the answer is:
target
'mark' is the definition.
('target' can be a synonym of 'mark')
'on protective coat receive' is the wordplay.
'on' is a charade indicator (letters next to each other).
'protective coat' becomes 'tar'.
'receive' becomes 'get' ('get' can be a synonym of 'receive').
'tar' put next to 'get' is 'TARGET'.
(Other definitions for target that I've seen before include "Something to aim for" , "Goal, objective" , "'Aim, goal (6)'" , "Object to be attained by archers (or fund raisers?)" , "Aim, ambition" .)