Historical records suggest that the term Non- Governmental Organizations (NGOs) came in to use in 1945. The term was coined during one of the conferences of The United Nations, as a measure to distinguish organizations from inter-governmental and member organizations. Though the term NGO received recognition only after 1945, studies suggest that several organizations were actively engaged against slavery, racism and women suffrage during the late eighteenth century.

Source: https://www3.fundsforngos.org/how-t.../1-1-what-is-a-non-governmental-organization/