Eureka | Definition of Eureka by Merriam-Webster
eu·​re·​ka | \ yu̇-ˈrē-kə How to pronounce eureka (audio) \

Definition of eureka

 (Entry 1 of 4)

used to express triumph on a discovery



Definition of eureka (Entry 2 of 4)

: 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 4)

: I have found (it) motto of California


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

Definition of Eureka (Entry 4 of 4)

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

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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 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, "When did Cleveland become confident it could land Sherwin-Williams’ new headquarters? Mayor Frank Jackson reveals the moment," 21 Feb. 2020 That eureka moment of mine with 5G in Providence came while using Verizon's network. Aaron Pressman, Fortune, "5G is supposed to be the future. But here’s what it’s like today," 24 Jan. 2020 Joan Smalls’s decorating eureka moment came at a fashionable dinner party. Marc Karimzadeh, ELLE Decor, "Supermodel Joan Smalls's Miami Aerie Gets a Luxe Beachy Makeover," 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, "The Age-Old Old Age Problem," 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, "Luxury safaris are trying to reinvent by getting greener and curbing an “Out of Africa” culture," 14 June 2019 Lacking those eureka bursts, Upheaval settles into story time. Daniel Immerwahr, The New Republic, "All Over the Map," 11 June 2019 Then the host had a eureka moment that changed television for good. Kyle Swenson,, "Jerry Springer changed TV forever. After 27 seasons, his daytime talk circus may be over.," 20 June 2018 The eureka moment worked, with the tiny symbol helping to imprint the brand name on consumer tastes. Kate Gibson, CBS News, "Kate Spade began with a simple wish: An unfussy handbag," 5 June 2018

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.

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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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Time Traveler for eureka

Time Traveler

The first known use of eureka was in 1603

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Cite this Entry

Eureka.” Dictionary, Merriam-Webster, Accessed 18 Sep. 2020.

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More Definitions for eureka

How to pronounce Eureka (audio)

English Language Learners Definition of eureka

used to express excitement when a discovery has been made

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