Companies lug in weapons (8)
I believe the answer is:
firearms
'weapons' is the definition.
(firearm is a kind of weapon)
'companies lug in' is the wordplay.
'companies' becomes 'firms' (I've seen this before).
'lug' becomes 'ear' (I've seen this before).
'in' means one lot of letters goes inside another.
'firms' enclosing 'ear' is 'FIREARMS'.
(Other definitions for firearms that I've seen before include "Rifles, guns, pistols etc" , "they can kill people" , "Weaponry" , "Weapons" , "Portable guns" .)