Euclid

American  

[yoo-klid] / ˈju klɪd /

noun

1. flourished c300 b.c., Greek geometrician and educator at Alexandria.

2. a city in NE Ohio, near Cleveland.

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Euclid British  

/ juːˈklɪdɪən, ˈjuːklɪd /

noun

1. 3rd century _bc , Greek mathematician of Alexandria; author of Elements, which sets out the principles of geometry and remained a text until the 19th century at least

2. the works of Euclid, esp his system of geometry

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Euclid Scientific  

/ yo̅o̅′klĭd /

1. Greek mathematician whose book, Elements, was used continuously until the 19th century. In it he organized and systematized all that was known about geometry. Euclid's systematic use of deductions and axioms was widely regarded as a model working method and influenced mathematicians and scientists for over two thousand years.

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Euclid Cultural  

1. An ancient Greek mathematician; the founder of the study of geometry. Euclid's Elements is the basis for modern school textbooks in geometry. One of the basic statements, or postulates, of Euclid's geometry is that if a line and a point separate from it are given, only one line parallel to the first line can pass through the point.

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Discover More

Albert Einstein used other approaches to geometry to derive the theory of relativity. These “non-Euclidean geometries” deny Euclid's postulate about parallel lines.

Other Word Forms

• Euclidean
  adjective

Example Sentences

See Examples For:

Euclid

The European Space Agency launched the Euclid space telescope in 2023 to investigate the universe during this pivotal era.

From Science Daily ● Jul. 9, 2026

Graduate students today know more math than Euclid, but that doesn’t make them greater mathematicians.

From The Wall Street Journal ● Feb. 6, 2026

These include missions such as the European Space Agency's Euclid spacecraft and observations from the Vera C. Rubin Observatory in Chile.

From Science Daily ● Dec. 25, 2025

Several local residents have complained about round-the-clock beeping and humming emitted by the self-driving cars as they make their way to two charging stations near the intersection of Euclid Street and Broadway.

From Los Angeles Times ● Nov. 24, 2025

He says that the two of us walked up to the house on Euclid Avenue one evening.

From "Becoming" by Michelle Obama