Republic of India vs British Commonwealth

Republic of India and British Commonwealth both are nouns.

Word	Noun	Adjective	Verb	Adverb
Republic of India	Yes	No	No	No
British Commonwealth	Yes	No	No	No

Republic of India (noun)	British Commonwealth (noun)
a republic in the Asian subcontinent in southern Asia; second most populous country in the world; achieved independence from the United Kingdom in 1947	an association of nations consisting of the United Kingdom and several former British colonies that are now sovereign states but still pay allegiance to the British Crown