OAS vs world organization

OAS and world organization both are nouns.

Word	Noun	Adjective	Verb	Adverb
OAS	Yes	No	No	No
world organization	Yes	No	No	No

As nouns, world organization is a hypernym of OAS; that is, world organization is a word with a broader meaning than OAS:

OAS: an association including most countries in the western hemisphere; created in 1948 to promote military and economic and social and cultural cooperation
world organization: an international alliance involving many different countries

OAS (noun)	world organization (noun)
an association including most countries in the western hemisphere; created in 1948 to promote military and economic and social and cultural cooperation	an international alliance involving many different countries