Parent Over Shoulder. Used when you're talking to somebody online about a personal topic, and a parent decides to check up on what you're doing. When the person on the other side of the screen sees this message, they should stop what they're talking about and start a pretend/different topic.
Mexican Slang. Derived from the Spanish word, “pues” translating to “well.”
An acronym for "Piece of shit". This is pronounced "Poss". This can be used to insult someone who is not showing you any respect or it can be used to describe something that does not work properly.
a) That idiot kept bothering me so I called him a POS!
b) This computer keeps giving me problems! It's a POS!