TAKE IT EASY

The phrase “take it easy” has several different meanings, and it's not always easy to tell between them from context. Referring specifically to the standalone phrase (grammatically, an imperative), not to the use of the verbal expression in general.

• I'm going on a holiday. — Take it easy for a week, you deserved it. (the usual verbal meaning)
•  I'm leaving, bye. — Take it easy. (≈ “have a nice time”)
• I'm going to hit someone. — Hey, take it easy, man! (≈ “keep your cool”)

What clues can distinguish the friendly use (have a nice time) from the reproachful use (keep calm)?
Are there other meanings to consider? Are there regional variations?

Answers

All uses of take it easy you can think of are nearly interchangeable with relax. (One wouldn't say just "relax" as a farewell, but in that use it's similar to "stay cool" or "have a good [relaxed] day".)

And uses where take it easy is literal imperative advice are not necessarily reproachful.

"Augh, I'll never get all these facts straight in time for the test! I'm going to fail, I know it!" "Whoa, take it easy. You can do this." All uses of take it easy you can think of are nearly interchangeable with relax. (One wouldn't say just "relax" as a farewell, but in that use it's similar to "stay cool" or "have a good [relaxed] day".)

And uses where take it easy is literal imperative advice are not necessarily reproachful.

"Augh, I'll never get all these facts straight in time for the test! I'm going to fail, I know it!" "Whoa, take it easy. You can do this."