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

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Synonyms & Antonyms for cuckoo

Synonyms: Noun

Synonyms: Adjective

Antonyms: Adjective

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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
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Recent Examples on the Web: Noun The young cuckoo wasp eats the nest’s rightful occupant and its food store. Meilan Solly, Smithsonian Magazine, "The World’s Most Interesting Insects," 29 Apr. 2020 Populations of the Suckley’s cuckoo bumblebee have seen declines of more than 90% over historic figures, according to the Center for Biological Diversity, the group pushing to protect the insect. oregonlive, "Environmental group seeks endangered species protection for rare parasitic bumblebee, last seen in Oregon," 24 Apr. 2020 One unforgettable example comes from the greater ani, a South American species of cuckoo. Jenny Odell, The Atlantic, "Why Birds Do What They Do," 16 May 2020 The cable networks are broadcasting Donald Trump’s cloud-cuckoo-land daily briefings filled with imaginary Covid-19 cures and mythical supplies of coronavirus tests. Walter Shapiro, The New Republic, "Stop Panicking About Joe Biden," 8 Apr. 2020 Each spring and fall, the cuckoo uses river corridors as routes to travel between its wintering and breeding grounds. Susan Montoya Bryan, azcentral, "US identifies habitat critical for survival of rare songbird," 29 Feb. 2020 So if there is something that the president does which is cuckoo, that’s our insurance policy. Time, "Mike Bloomberg Wants to Fix America. But Can He Fix the Democrats?," 2 Mar. 2020 Federal biologists describe the cuckoo as an elusive species. Susan Montoya Bryan, azcentral, "US identifies habitat critical for survival of rare songbird," 29 Feb. 2020 The three weights indicate that this is a musical clock, with one weight powering the time and the other powering the cuckoo calling and any animation. oregonlive, "French urn, Pittsburgh lamp could be worth thousands: Today’s Collectibles," 1 Feb. 2020 Recent Examples on the Web: Adjective In another photo, the bunting is retreating in terror, as the cuckoo squawks directly in its face. Fox News, "Funny photos show cuckoos fighting off smaller birds for space," 24 June 2020 Spring training is going to be cuckoo for more than a few clubs. WSJ, "Hot Stove Meets Hot Garbage! Baseball Can’t Slam Lid on Astros Trash Can Sign-Stealing Scam," 23 Jan. 2020 The movie is a colorful, cuckoo-crazy, sometimes funny, often bewildering experience. Katie Walsh, Detroit Free Press, "‘Angry Birds 2’ is chaotic, occasionally thoughtful," 12 Aug. 2019 In this very cuckoo moment, Double Shot turned sincere, even sad. Darren Franich,, "In praise of the goofy, shocking, endearing Double Shot at Love finale," 28 June 2019 These cuckoo conspiracy theories are symptomatic of a shift in global values from the optimism of the 1990s, when America’s liberal democracy was universally admired, to the current era of fear and anger, when democracy is in retreat. Trudy Rubin,, "Roseanne's other twisted tweet of the week. (The one you didn't already read about) | Trudy Rubin," 1 June 2018 Celebrities and designers are cuckoo for them: Adele performs with one in her pocket, Kim Kardashian West designed her fragrance after their unique forms, and Mary-Kate and Ashley Olsen offered them to guests at The Row’s most recent fashion show. Rachel Waldman, Vogue, "This Model-Turned-Baker Makes Otherworldly Candy Crystals," 6 Apr. 2018 Alva’s just one of many San Antonians who’s downright cuckoo for Funko Pops. René A. Guzman, San Antonio Express-News, "San Antonio one of many cities madly collecting Funko Pop! figures," 6 Apr. 2018 In cases like these, in which subjects are claiming harm from a cuckoo experiment, the system is set up to punish the institution rather than give redress to the subject. Marisa Taylor, Washington Post, "Unregulated Herpes Experiments Expose ‘Black Hole’ Of Accountability," 21 Dec. 2017

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.

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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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Time Traveler for cuckoo

Time Traveler

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

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Statistics for cuckoo

Last Updated

15 Jun 2020

Cite this Entry

“Cuckoo.” Dictionary, Merriam-Webster, Accessed 9 Jul. 2020.

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More Definitions for cuckoo


How to pronounce cuckoo (audio) How to pronounce cuckoo (audio)

English Language Learners Definition of cuckoo

 (Entry 1 of 2)

: a type of bird that lays its eggs in the nests of other birds and that has a call that sounds like its name



English Language Learners Definition of cuckoo (Entry 2 of 2)

informal + old-fashioned
: silly or crazy
: very enthusiastic


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

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More from Merriam-Webster on cuckoo

Thesaurus: All synonyms and antonyms for cuckoo

Rhyming Dictionary: Words that rhyme with cuckoo

Spanish Central: Translation of cuckoo

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

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