POS can have different meanings depending on the context. In technology and business, it usually stands for Point of Sale, which refers to the system or machine used in stores to process payments. In texting or online chats, POS may sometimes mean Parent Over Shoulder, used to warn someone that a parent is nearby. In slang, it can also be used as an insult, meaning “Piece of Sh*t.” The correct meaning depends on how and where the term is used.