military vs insignia of rank

military and insignia of rank both are nouns.

Word	Noun	Adjective	Verb	Adverb
military	Yes	Yes	No	No
insignia of rank	Yes	No	No	No

military (noun)	insignia of rank (noun)
the military forces of a nation	an insignia worn on a military uniform

military (adjective)	insignia of rank (adjective)
associated with or performed by members of the armed services as contrasted with civilians
characteristic of or associated with soldiers or the military
of or relating to the study of the principles of warfare