no joke

no joke

1. Something that must or should be taken seriously. Skipping your yearly assessment is no joke, Daniel. You could get fired for that!
2. I agree; you're right; that's true. A: "Wow, that exam was brutally difficult." B: "Yeah, no joke!"
See also: joke, no
Farlex Dictionary of Idioms.

no joke

a serious matter. It's no joke when you miss the last train. It's certainly no joke when you have to walk home.
See also: joke, no
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

no joke

Also, no laughing matter. A serious issue, as in Missing the last flight out was no joke, or This outbreak of flu is no laughing matter. The first term dates from about 1800, and the variant from the second half of the 1500s.
See also: joke, no
The American Heritage® Dictionary of Idioms by Christine Ammer.
See also:
  • I feel that
  • I feel you
  • feel someone
  • crack a joke
  • bring something to light
  • bring to light
  • in on the joke
  • running joke
  • inside joke
  • be headed for (something)