A general rule covering new equipment produced by a major employer (6)
I believe the answer is:
cannon
'equipment produced by a major employer' is the definition.
I can't tell whether this definition defines the answer.
'a general rule covering new' is the wordplay.
'a general rule' becomes 'canon' (I've seen this before).
'covering' is an insertion indicator.
'new' becomes 'n'.
'canon' placed around 'n' is 'CANNON'.
Can you help me to learn more?
(Other definitions for cannon that I've seen before include "shot playing billiards" , "Old naval gun" , "One of the big guns" , "Heavy ordnance" , "Howitzer" .)