In Instagram's diverse landscape, there are lots of slang terms to be found. PMO is one of such acronyms. Did you know what does pmo mean on instagram? If No, Then don't worry, PMO has two meanings depending on the context of its usage. 1. Put Me On(PMO) - That indicates a desire to connect with fellow Instagram users. 2. Pisses Me Off(PMO) - It indicates your annoyance towards someone or something.