Also found in: Acronyms.
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!"
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
a serious matter. It's no joke when you miss the last train. It's certainly no joke when you have to walk home.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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.
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.