armed forces vs operational

armed forces is a noun but operational is not a noun.

Word	Noun	Adjective	Verb	Adverb
armed forces	Yes	No	No	No
operational	No	Yes	No	No

armed forces (noun)	operational (noun)
the military forces of a nation

armed forces (adjective)	operational (adjective)
	(military) of or intended for or involved in military operations
	pertaining to a process or series of actions for achieving a result
	being in effect or operation
	fit or ready for use or service