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Synonyms

madcap

American  
[mad-kap] / ˈmædˌkæp /

adjective

  1. wildly or heedlessly impulsive; reckless; rash.

    a madcap scheme.


noun

  1. a madcap person.

madcap British  
/ ˈmædˌkæp /

adjective

  1. impulsive, reckless, or lively

"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

noun

  1. an impulsive, reckless, or lively person

"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

Etymology

Origin of madcap

First recorded in 1580–90; mad + cap 1

Explanation

Madcap things are done in a foolish, rash, or impulsive way, without planning or thought. Your madcap adventure might include a spur-of-the-moment bus ride to a nearby city without enough money in your pocket to buy lunch. The adjective madcap, which can simply mean "impetuous," can also have a sense of "funny and eccentric." A movie that's described as a madcap comedy will probably be full of broad slapstick and laugh-out-loud physical humor. Madcap, dating from the 16th century, originally meant "lunatic" or "crazy person," from the "head" sense of cap — in other words, a madcap was a "crazy head."

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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.

See Examples For:

Bree begins the film desperately wanting gender-affirming surgery, so much so that her urgency incites the film’s madcap mumblecore events.

From Salon Aug. 28, 2026

New reads abound for your vacation tote throughout the weeks of July, with fiction picks featuring a Carnival cruise casualty, a highly entertaining jewel heist at the Waldorf-Astoria, and a Soviet-era madcap adventure.

From Los Angeles Times Jul. 2, 2026

In a staggering contest of 13 tries and 90 points, Gregor Townsend's men were astonishing in every way until a madcap endgame that saw France run in a battery of tries.

From BBC Mar. 7, 2026

The Warriors had led until the end of the third quarter, before a madcap finish saw 12 lead changes, with regular time ending 101-101.

From Barron's Mar. 6, 2026

I think of her madcap, joyful dresses, of her dust-covered bedroom.

From "The Cruel Prince" by Holly Black

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