The fathead puts weapons in agricultural holdings (5)
I believe the answer is:
farms
'weapons in agricultural holdings' is the definition.
The definition and answer can be both man-made objects as well as being plural nouns.
Maybe you can see a link between them that I can't see?
'the fathead puts' is the wordplay.
'the fathead' becomes 'f' (head letter of 'fat').
'puts' becomes 'arms' (I can't explain this - if you can you should believe this answer much more).
'f'+'arms'='FARMS'
Can you help me to learn more?
(Another definition for farms that I've seen is " Works the land".)