Not joking (7)

I believe the answer is:

serious

(Other definitions for serious that I've seen before include "Earnest - important" , "Solemn, thoughtful" , "Stern" , "Earnest; vital" , "Earnest, sincere" .)

I've seen this clue in the USA Today.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.