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Synonyms

eureka

1 American  
[yoo-ree-kuh, yuh-] / yʊˈri kə, yə- /

interjection

  1. (initial capital letter) I have found (it): the reputed exclamation of Archimedes when, after long study, he discovered a method of detecting the amount of alloy mixed with the gold in the crown of the king of Syracuse.

  2. (used as an exclamation of triumph at a discovery.)

Eureka 2 American  
[yoo-ree-kuh, yuh-] / yʊˈri kə, yə- /

noun

  1. a city in NW California.

eureka British  
/ jʊˈriːkə /

interjection

  1. an exclamation of triumph on discovering or solving something

"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
Eureka! Cultural  

  1. A Greek word meaning “I have found it!” An exclamation that accompanies a discovery: “When she finally located the rare book, the scholar cried, ‘Eureka!’” (See Archimedes.)

Etymology

Origin of eureka

1560–70; < Greek heúrēka, 1st person singular perfect indicative of heurískein to find, discover

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.

I think my first eureka moment was when I was traveling in sub-Saharan Africa on the Ivory Coast doing a site visit.

From Barron's • Mar. 5, 2026

The results were no eureka moment for luxury and might lead to caution prevailing among investors, Jefferies analysts wrote in a note to clients.

From The Wall Street Journal • Jan. 28, 2026

"It's one of those eureka moments that you think 'nature is trying to tell us something here.'"

From Science Daily • Oct. 16, 2025

This is a eureka moment for astronomers as they just found a new way to track Venusian weather over the past decade - the longest duration of observation ever.

From Space Scoop • Jul. 8, 2025

It was those birds that had given him one of his eureka moments about natural selection.

From "Charles and Emma: The Darwins' Leap of Faith" by Deborah Heiligman

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.