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Synonyms

brainless

American  
[breyn-lis] / ˈbreɪn lɪs /

adjective

  1. mentally weak; foolish; witless; stupid.

brainless British  
/ ˈbreɪnlɪs /

adjective

  1. stupid or foolish

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • brainlessly adverb
  • brainlessness noun

Etymology

Origin of brainless

First recorded in 1400–50, brainless is from the late Middle English word braynles. See brain, -less

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In 1977, after the release of the album Zombie, which satirised government soldiers as obedient, brainless enforcers, his compound in the main city, Lagos, was raided.

From BBC • Jan. 29, 2026

So it goes throughout this visually mammoth but brainless audio-visual excursion.

From The Wall Street Journal • Dec. 17, 2025

A stunned England woke Sunday to savage criticism after their meek capitulation in the first Ashes Test, branded "brainless" and "damaged" by former greats after their cavalier approach backfired.

From Barron's • Nov. 23, 2025

The dialogue was more dignified: no brainless chatter or mawkish introductions.

From New York Times • Jun. 17, 2024

Penelope replied: “He is no fool; he sees how it could be. Never were mortal men like these for bullying and brainless arrogance!”

From "The Odyssey" by Homer

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.