U. S. Army vs armed services

U. S. Army and armed services both are nouns.

Word	Noun	Adjective	Verb	Adverb
U. S. Army	Yes	No	No	No
armed services	Yes	No	No	No

U. S. Army (noun)	armed services (noun)
the army of the United States of America; the agency that organizes and trains soldiers for land warfare	the military forces of a nation