Compact weapons rejected (4)
I believe the answer is:
snug
'compact' is the definition.
(thesaurus)
'weapons rejected' is the wordplay.
'weapons' becomes 'guns' (gun is a kind of weapon).
'rejected' shows that the letters should be reversed in order.
'guns' in reverse letter order is 'SNUG'.
(Other definitions for snug that I've seen before include "Cosy retreat" , "Intimate" , "Cosy and comfortable" , "Comfortable -- small secluded room" , "Cosy room" .)