brainless

adjective

brain·​less ˈbrān-ləs How to pronounce brainless (audio)
Synonyms of brainlessnext
1
: devoid of intelligence : stupid
a brainless decision
2
: not demanding understanding or intelligence : dull, stupefying
a brainless task
brainless repetition
3
: lacking a brain
brainless organisms
brainlessly adverb
brainlessness noun

Synonyms of brainless

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Examples of brainless in a Sentence

He thought most of his coworkers were brainless. The plot of the new movie is brainless and the acting is terrible.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
There's really no way to prep for the show — basically, just don't be brainless. — Lindsay Soll, EW.com, 25 July 2025 That Malice can be heartless and brainless need not be a problem; some of my favorite shows are mean and stupid, and downright gleeful about it. — Angie Han, HollywoodReporter, 14 Nov. 2025 An oyster, immobile and nearly brainless, is hardly even an animal, despite what the taxonomists tell us. — Peter Rubin, Longreads, 9 Jan. 2024 So, what can the neuronal activity of a tiny, brainless creature possibly tell us about the evolution of our own complex brains? — Elizabeth Rayne, Ars Technica, 15 June 2024 See All Example Sentences for brainless

Word History

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of brainless was in the 15th century

Rhymes for brainless

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Browse Nearby Words

brainish
brainless
brain lock
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Cite this Entry

“Brainless.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/brainless. Accessed 8 Jul. 2026.

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Kids Definition

brainless

adjective
brain·​less ˈbrān-ləs How to pronounce brainless (audio)
: lacking intelligence
brainlessly adverb

More from Merriam-Webster on brainless

Nglish: Translation of brainless for Spanish Speakers

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