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brainfag

American

[breyn-fag] / ˈbreɪnˌfæg /

noun

Informal.

prolonged mental fatigue.

Etymology

Origin of brainfag

First recorded in 1850–55; brain + fag ²

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.