Arms depot (7)
I believe the answer is:
arsenal
'arms depot' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for arsenal that I've seen before include "Where the guns are and who are The Gunners are" , "Munitions store and English football team" , "Place where guns and ammunition are stored" , "2014 and 2015 FA Cup winners" , "Weapons/ammo store" .)