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FAFO

American

[fah-foh] / ˈfɑ foʊ /

Or fafo or FaFo

abbreviation

Vulgar, Slang. fuck around and find out (used as a warning or challenge to indicate that unwanted behavior will result in dire consequences).

verb (used without object)

FAFOed, FAFOing

Vulgar, Slang. fuck around and find out: to engage in behavior that results in dire consequences.
Computers. fuck around and find out: to seek, by trial and error or random exploration, to find out how something works.

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.