Enclosed (5)
I believe the answer is:
cased
'enclosed' is the definition.
(casing is a kind of enclosing)
This is the entire clue.
(Other definitions for cased that I've seen before include "Covered, protected; checked over (by robber)" , "Carefully inspected (for crime)" , "examined with intention to rob" , "Reconnoitred (sl.)" , "put in a box" .)