world organisation vs world organization

world organisation and world organization both are nouns.

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

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

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

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

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