system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Why does the word 'cool' remain cool for so long, and yet words like 'groovy' and 'rad' seem out of date in just a couple of decades?
gpt
Cool is more than just a word for something good. It does mean that, but it has other related uses.

It can refer to a "cool head" which is someone who doesn't get worked up about things, as opposed to a hothead.

This calm demeanor is frequently interpreted by onlookers as confidence or surity, which are generally desirable traits.

Also, "cool" is accepted use for more moderate levels of desirability. "That was cool" can express anything from relatively mild approval to outright amazement depending on inflection.

Other slang terms, like radical or tubular were necessarily used to represent more dramatic emotions regarding the subject. This likely results in a sort of burnout of the words because people get sick of here how *everything* is so great, while "cool" is just, well, cool.