Proper pocket (11)
I believe the answer is:
appropriate
I believe this clue is a double definition.
'proper' is the first definition.
(similar in meaning)
'pocket' is the second definition.
(I've seen this before)
(Other definitions for appropriate that I've seen before include "Steal - fitting" , "Fit" , "Trouser" , "Take; suitable" , "lift" .)