Possibly bears a weapon (5)
I believe the answer is:
sabre
'a weapon' is the definition.
(sabre is a kind of weapon)
'possibly bears' is the wordplay.
'possibly' is an anagram indicator.
'bears' with letters rearranged gives 'SABRE'.
(Other definitions for sabre that I've seen before include "Sword (that may be rattled)" , "Large wasp" , "Heavy cavalry sword" , "Sword with curved blade" , "Walt --, cartoonist" .)