military machine vs caisson

military machine and caisson both are nouns.

Word	Noun	Adjective	Verb	Adverb
military machine	Yes	No	No	No
caisson	Yes	No	No	No

military machine (noun)	caisson (noun)
the military forces of a nation	large watertight chamber used for construction under water
	an ornamental sunken panel in a ceiling or dome
	a chest to hold ammunition
	a two-wheeled military vehicle carrying artillery ammunition