There are some similar expressions. I'm chilling has a positive meaning, but if you want to tell someone to calm down, you can say "Chill out" or just "chill". All of these expressions are slang. :) If you want to chat some time, let me know. :) Kevin

It means relaxing or enjoying calmness. You are chilling/chillin', as if you've been put in a fridge.

Ohh I am sory , I wrote wrong That is true , " I'm chillin"