United States Marine Corps vs US Marine Corps

United States Marine Corps and US Marine Corps both are nouns.

Word	Noun	Adjective	Verb	Adverb
United States Marine Corps	Yes	No	No	No
US Marine Corps	Yes	No	No	No

As nouns, United States Marine Corps and US Marine Corps are synonyms defined as:

United States Marine Corps and US Marine Corps: an amphibious division of the United States Navy

Other synonyms of United States Marine Corps include Marine Corps, Marines, United States Marines, USMC.

United States Marine Corps (noun)	US Marine Corps (noun)
an amphibious division of the United States Navy	an amphibious division of the United States Navy