rank and file vs armed forces

rank and file and armed forces both are nouns.

Word	Noun	Adjective	Verb	Adverb
rank and file	Yes	No	No	No
armed forces	Yes	No	No	No

rank and file (noun)	armed forces (noun)
the ordinary members of an organization (such as the enlisted soldiers of an army)	the military forces of a nation
people who constitute the main body of any group