PMO has multiple meanings depending on the context:
- In internet slang and texting, PMO commonly stands for "Piss Me Off," "Pissing Me Off," or "Pissed Me Off," used to express frustration or anger
- In a business and project management context, PMO stands for Project Management Office. This is a department or team within an organization responsible for establishing and maintaining project management standards, processes, and governance. The PMO oversees project portfolios, ensures projects are completed on time and within budget, and supports project managers by providing guidance, resources, and strategic alignment with organizational goals
- Another less common slang meaning is "Put Me On," meaning "hook me up" or "link me up" with someone
The two main uses are thus very different: one informal and expressive in online communication, the other formal and organizational in business/project management.