eu·​re·​ka | \ yu̇-ˈrē-kə How to pronounce eureka (audio) \

Definition of eureka

 (Entry 1 of 3)

used to express triumph on a discovery



Definition of eureka (Entry 2 of 3)

: marked by usually sudden triumphant discovery a eureka moment


Greek verb
eu·​re·​ka | \ yu̇-ˈrē-kä How to pronounce eureka (audio) \

Definition of eureka (Entry 3 of 3)

: I have found (it) motto of California

Did you know?

When people exclaim Eureka! they are reenacting a legendary event in the life of the Greek mathematician and inventor Archimedes. While wrestling with the problem of how to determine the purity of gold, he made the sudden realization that the buoyancy of an object placed in water is equal in magnitude to the weight of the water the object displaces. According to one popular version of the legend, he made his discovery at a public bathhouse, whereupon he leapt out of his bath, exclaimed “Heureka! Heureka!” (“I have found it!”), and ran home naked through the streets. The absence of a contemporary source for this anecdote has done nothing to diminish its popularity over the centuries.

Examples of eureka in a Sentence

Recent Examples on the Web: Adjective Standing in the living room of a tiny Tempe apartment is kind of a weird place to have a eureka moment. Bill Goodykoontz, The Arizona Republic, 24 Nov. 2021 In 2014, siblings Yasameen and Sheilla Sajady had a eureka moment at the family lunch table. Nicole Hvidsten, Star Tribune, 7 May 2021 The eureka moment for negotiators working to keep Sherwin-Williams’ headquarters in Cleveland came nearly two months ago, Mayor Frank Jackson disclosed this week. Robert Higgs, cleveland, 21 Feb. 2020 That eureka moment of mine with 5G in Providence came while using Verizon's network. Aaron Pressman, Fortune, 24 Jan. 2020 Joan Smalls’s decorating eureka moment came at a fashionable dinner party. Marc Karimzadeh, ELLE Decor, 8 Aug. 2019 That juxtaposition sparked Eheart’s eureka moment: build communities where foster families and older adults live together, helping each other. Abigail Jones, Newsweek, 24 Sep. 2014 Driving between his properties in Zambia back in 2010, Green Safaris’ founder Vincent Kouwenhoven’s eureka moment came when switching off his Land Rover to watch a pack of lions. Lee Middleton, Quartz Africa, 14 June 2019 Lacking those eureka bursts, Upheaval settles into story time. Daniel Immerwahr, The New Republic, 11 June 2019 See More

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

First Known Use of eureka


1603, in the meaning defined above


1948, in the meaning defined above

History and Etymology for eureka


Greek heurēka I have found, from heuriskein to find; from the exclamation attributed to Archimedes on discovering a method for determining the purity of gold — more at heuristic

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Cite this Entry

“Eureka.” Dictionary, Merriam-Webster, Accessed 28 Jun. 2022.

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Eureka geographical name

Eu·​re·​ka | \ yu̇-ˈrē-kə How to pronounce Eureka (audio) \

Definition of Eureka

city and port on Humboldt Bay in northwestern California population 27,191

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