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Synonyms

harebrained

American  
[hair-breynd] / ˈhɛərˌbreɪnd /
Or hairbrained

adjective

  1. giddy; reckless.

    Synonyms:
    dimwitted, half-baked, scatterbrained, rattlebrained

harebrained British  
/ ˈhɛəˌbreɪnd /

adjective

  1. rash, foolish, or badly thought out

    harebrained schemes

"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

  • harebrainedly adverb
  • harebrainedness noun

Etymology

Origin of harebrained

First recorded in 1545–55; hare + brained

Explanation

Something that's harebrained is reckless or foolish. Sometimes, harebrained ideas work out just fine — several people have survived trips over Niagara Falls in a barrel, for example. If you have what you think is a great idea, but someone else calls it a harebrained scheme, it means they think you'd be a fool to try it. For example, your harebrained plan to ride your bike on the highway is bound to get you in trouble. The 16th century harebrained came from the earlier harebrain, "giddy or reckless person," from the common impression of a rabbit or a hare as being nervous and skittish.

Keep Reading on Vocabulary.com

Vocabulary lists containing harebrained

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.

“It was the most harebrained operation I’d seen in my 38 years with the U.S. government,” Nagy said, referring to the methods used this year.

From Salon • Dec. 16, 2025

The scheme seemed as harebrained as it was cruel, and Martinez offered little to lend clarity.

From Los Angeles Times • Jun. 19, 2025

They seeded suspicion and harebrained ideas of alternative cures, some toxic.

From Slate • Nov. 7, 2024

Probably it was always a harebrained scheme, though bearing in mind the atrocities to come it is hard not to sympathize.

From Washington Post • Jan. 5, 2023

Knowing Juanita and her quixotic ways, this could turn into one of her many harebrained schemes.

From "Summer of the Mariposas" by Guadalupe García McCall