brain·less | \ˈbrān-ləs \

Definition of brainless 

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

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Other Words from brainless

brainlessly adverb
brainlessness noun

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

Not the brainless brutes of our imaginations, Neanderthals apparently used advanced hunting techniques to stalk and kill their prey, a new study suggests. Doyle Rice, USA TODAY, "How to hunt like a Neanderthal: Ancient humans got up close with their prey," 26 June 2018 Well, in the land of brainless politicians, even no-brainer pieces of legislation sometimes go nowhere. Heather Knight,, "Car break-in crackdown bill made perfect sense. California lawmakers killed it," 15 June 2018 In the last two decades, researchers have identified sleep-like behavior in fruit flies, tiny nematodes, and even a brainless jellyfish. Michael Greshko, National Geographic, "Brainless Creatures Can Do Some Incredibly Smart Things," 21 May 2018 Here are a few examples of brainless organisms that are actually pretty smart. Michael Greshko, National Geographic, "Brainless Creatures Can Do Some Incredibly Smart Things," 21 May 2018 What a heartless, wicked, brainless thing to do! . . Kathryn Schulz, The New Yorker, "Broadway’s Original Mansplainer," 23 Apr. 2018 The scientists found that this procedure rescued the brainless tadpoles from most of the usual defects. Adam Rogers, WIRED, "Brainless Embryos Suggest Bioelectricity Guides Growth," 18 Mar. 2018 Why would anyone devote her life to a brainless, spineless, gutless group of parasites? Sarah Kaplan, Washington Post, "Tapeworms are brainless, spineless, gutless parasites — and this scientist loves them," 2 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'brainless.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of brainless

15th century, in the meaning defined above

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Statistics for brainless

Last Updated

21 Aug 2018

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

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English Language Learners Definition of brainless

: very stupid or silly

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