Joking apart! (9)
I believe the answer is:
seriously
(Other definitions for seriously that I've seen before include "Gravely" , "In a solemn and thoughtful manner" .)
I've seen this clue in The Guardian.
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.