Slang terms come and go, and if you keep using them, they will reveal your age. Things that are good can be the bee's knees, groovy, rad, or awesome, depending on the decade you're in. But good things can be cool, too, no matter what the decade. How did the word "cool" become immortal?
Linguist Arika Okrent and illustrator Sean O’Neill look into the history and usage of the slang word "cool." The exact meaning of the term has changed, but it has managed to hold onto a positive connotation over a long period of time. You have to admit that this video is pretty cool. -via Laughing Squid