cuck·​oo | \ ˈkü-(ˌ)kü How to pronounce cuckoo (audio) , ˈku̇- How to pronounce cuckoo (audio) \
plural cuckoos

Definition of cuckoo

 (Entry 1 of 3)

1 : a largely grayish-brown European bird (Cuculus canorus) that is a parasite given to laying its eggs in the nests of other birds which hatch them and rear the offspring broadly : any of a large family (Cuculidae of the order Cuculiformes) to which this bird belongs
2 : the call of the cuckoo
3 : a silly or slightly crackbrained person


cuckooed; cuckooing; cuckoos

Definition of cuckoo (Entry 2 of 3)

transitive verb

: to repeat monotonously as a cuckoo does its call



Definition of cuckoo (Entry 3 of 3)

1 : of, relating to, or resembling the cuckoo
2 : deficient in sense or intelligence : silly

Illustration of cuckoo

Illustration of cuckoo


cuckoo 1

In the meaning defined above

Synonyms & Antonyms for cuckoo

Synonyms: Noun

Synonyms: Adjective

Antonyms: Adjective

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The cuckoo bird is so named for its one-note song, which in Middle English was represented as cuccu in imitation. Figurative use of cuckoo, which exists as an adjective meaning "crazy" or "weak in intellect or common sense," and as a noun for a person who can be described as such, may be an allusion to the bird's eponymous (and monotonous) call. But it may also be inspired by a peculiar habit exhibited by some species, in which a female will lay her eggs in the nest of another bird, to be hatched by that bird. In Old French, the name of the bird, cucu, also refers to a husband whose wife is unfaithful. That sense is believed to come from the female cuckoo bird's habit in some species of changing mates, or to the same egg-laying habit that influenced English figurative use. Cucu is also the source of English cuckold.

Examples of cuckoo in a Sentence

Noun one cuckoo at the campground tried to boil soup in a plastic cup didn't want to be among those cuckoos who race around the mall the day before Christmas Adjective a cuckoo woman who wandered around town carefully gathering up useless trash offered a completely cuckoo suggestion for using the defunct strip mall
Recent Examples on the Web: Noun The river is also home to the willow flycatcher and yellow-billed cuckoo. Meryl Kornfield, Anchorage Daily News, 23 July 2022 The traditional finery is ornate and the souvenir cuckoo clocks even more so. Matthew Kronsberg, WSJ, 17 June 2022 For example, Ludwig van Beethoven’s 6th Symphony simulates a cuckoo with a clarinet, a nightingale with a flute, and a quail with an oboe. Stephen Humphries, The Christian Science Monitor, 6 June 2022 Daddy's little girl is all grown up, which makes Martin's George Banks a little cuckoo. Hilary Weaver, ELLE, 1 June 2022 Some, like the common cuckoo, are egg-tossing executioners; others, like the cowbirds that Hauber studies, let their host siblings survive, but still jostle them out of the way to beg, loudly and insistently, for food. Katherine J. Wu, The Atlantic, 26 Oct. 2021 Today, grazing and ranching, dams, and water withdrawal for development pose the greatest threats to the cuckoo. Lindsey Botts, The Arizona Republic, 18 Oct. 2021 As dawn broke and the rising sun lit the top of the canopy, the cuckoo finally arrived to investigate. New York Times, 12 Jan. 2021 The cuckoo’s numbers have been shrinking in recent years, but conservation scientists are unsure why. New York Times, 12 Jan. 2021 Recent Examples on the Web: Adjective In the midst of such cuckoo-ness, my son, Isaac, and daughter-in-law, Lennon, had the courage to bring a child into this world. New York Times, 15 Mar. 2022 Generations later, those simple handmade objects evolved further into cuckoo clocks, music boxes and movie projectors. Pat Mcdonogh, The Courier-Journal, 12 Jan. 2022 After keeping up a cuckoo-bananas schedule through 2020 and 2021, the band will be taking an extended period of rest, Big Hit Music announced on Twitter. Bethy Squires, Vulture, 6 Dec. 2021 In some areas of the Coronado National Forest, Bugbee has witnessed herds of unbranded cattle wreaking havoc on cuckoo habitat. Lindsey Botts, The Arizona Republic, 23 Nov. 2021 For a weary cuckoo chick, a few extra strength-training sessions might make all the difference between booting its fourth and final nest-mate and having to share its chow. Katherine J. Wu, The Atlantic, 26 Oct. 2021 To say the world had gone cuckoo for Christian Dior would not be an overstatement; reports show that by 1949, Dior’s confections for the closet accounted for nearly three-quarters of France’s fashion exports. Lilah Ramzi, Vogue, 28 Sep. 2021 There are several species of cuckoo bees in Oregon. oregonlive, 27 Aug. 2021 That is truly cuckoo bananas — and that is saying something with this show., 4 Aug. 2021 See More

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

First Known Use of cuckoo


13th century, in the meaning defined at sense 1


1648, in the meaning defined above


1627, in the meaning defined at sense 1

History and Etymology for cuckoo


Middle English cuccu, of imitative origin

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The first known use of cuckoo was in the 13th century

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Last Updated

5 Aug 2022

Cite this Entry

“Cuckoo.” Dictionary, Merriam-Webster, Accessed 18 Aug. 2022.

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More Definitions for cuckoo


cuck·​oo | \ ˈkü-kü How to pronounce cuckoo (audio) , ˈku̇- \
plural cuckoos

Kids Definition of cuckoo

1 : a grayish brown European bird that lays eggs in the nests of other birds which hatch and raise them
2 : the call of the cuckoo

More from Merriam-Webster on cuckoo

Nglish: Translation of cuckoo for Spanish Speakers Encyclopedia article about cuckoo


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