Abbreviation for "later" in the context of goodbye or see you soon. Usually used with a really good friend in a rush.
Derrick: "Okay, so we're gonna meet up at the movies around 7. We're seeing the new Avengers"
Barry: "Dope!" I'm gonna go home, take a shower, and get ready."
Derrick: "For, sure bro! See you then."
Barry: "Sounds good. Alright, late!"