Organisation and organization mean the same thing. They are alternative spellings of the same word, both being used in British English and only one being used in American English.

The meaning of ORGANIZATION is the act or process of organizing or of being organized. How to use organization in a sentence.

An organization or organisation (Commonwealth English; see spelling differences) is an entity —such as a company, or corporation or an institution (formal organization), or an association …

Meaning of organization in English organization noun (UK usually organisation) uk / ˌɔː.ɡ ə n.aɪˈzeɪ.ʃ ə n / us / ˌɔːr.ɡ ə n.əˈzeɪ.ʃ ə n /

[countable] a group of people who form a business, club, etc. together in order to achieve a particular aim. She's the president of a large international organization. He works with local …

She is responsible for the organization of the party. The new president plans to make changes to the company's organization. You have a lot of good ideas in this paper, but there's no …

An organization is a group of people who work together, like a neighborhood association, a charity, a union, or a corporation. You can use the word organization to refer to group or …

An organization is an official group of people, for example a political party, a business, a charity, or a club. Most of these specialized schools are provided by voluntary organizations. ...a report …

The British and the Commonwealth countries most often use the spelling organisation. In some cases, a writer of American English might include the “s” version, organisation.

Is it an organization or organisation? Both spellings are correct, but “organization” is typically used in American English, while “organisation” is more common in British English.