As nouns the difference between ordnance and armament
is that ordnance is military equipment, especially weapons and ammunition while armament is a body of forces equipped for war.
ordnance
English
Noun
(
en noun)
military equipment, especially weapons and ammunition.
artillery.
Usage notes
The British , now a civilian agency, retains its name from its origin as a military topographic survey of Britain during the Napoleonic Wars.
This word is often confused with ordinance, which is a law or legal statute.
Related terms
* unexploded ordnance
armament
Noun
(
en noun)
A body of forces equipped for war.
(military, naval) All the cannon and small arms collectively, with their equipments, belonging to a ship or a fortification.
Any equipment for resistance.
The process of building up military capacity.