Legit

Shortened for "legitimate" with broader meaning. While it can refer to something real, or more specifically not fake/phony (or bootleg) (1), it can also denote "rightness", either moral, legal, or otherwise. In this sense it is similar to αριστος (2). It can also refer to something that is simply true (3).

1. "No, that's legit gold."
2. "Or how about I take my shit back and I don't beat you?" "That's legit."
3. "We were all late from gym, legit!"