Green’s Dictionary of Slang

1. (US black/teen) stand-offish, resentful.

1962

P. Crump Burn, Killer, Burn! 129: Are you chilled? [...] You don’t like me, do you, Guy?

2. (US campus) informal but sophisticated.

1995

Eble Campus Sl. Dec. 2: chilled – relaxed in a stylish way: ‘My friend wants to go to a restaurant with a chilled atmosphere.’.

3. relaxed.

2018

J.-P. Jordan Joys of War 83: I found out why he was more relaxed as he was putting the fuel into the [...] van: fuel nozzle in one hand and a joint in the other. [...] Well at least I knew the drive would be chilled .