To chill or stand at a spot (like a club or a street corner etc). To claim a spot. The term came from drug dealers on street corners, like light posts and street posts, and there you have it POST UP!
Synonyms for post up
On this page, you will find 30 slang terms related to post up. Some of the top words include: diesel, twist, Special K, blows, minted, and 25 more.