world organization vs international organisation

world organization and international organisation both are nouns.

Word	Noun	Adjective	Verb	Adverb
world organization	Yes	No	No	No
international organisation	Yes	No	No	No

As nouns, world organization and international organisation are synonyms defined as:

world organization and international organisation: an international alliance involving many different countries

Other synonyms of world organization include global organization, international organization, world organisation.

world organization (noun)	international organisation (noun)
an international alliance involving many different countries	an international alliance involving many different countries