hare-brained, hair-brained

The spellings hare-brained and hair-brained are both accepted. (The hyphen is preferred in Canadian spelling, but the terms may also be written without it.)

Hare-brained is the more common spelling and more accurately reflects the origin of the term, which was first used in the 16th century to describe a foolish person—one “with the brain of a hare”:

• “My desire is that none of you be so unadvised or harebrained …” (British historian Edward Hall, 1548)

The modifier is also applied to anything that might have been created by someone with the brain of a hare:

• Which of his hare-brained schemes are you willing to try?

Since hare was sometimes spelled haire or hair in 16th-century English, the spelling hair-brained also has a long history:

• In Shakespeare’s Henry VI, the English are described as “hairbrained slaves.”

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