ec·​cen·​tric·​i·​ty | \ ˌek-(ˌ)sen-ˈtri-sə-tē How to pronounce eccentricity (audio) \
plural eccentricities

Definition of eccentricity

1a : the quality or state of being eccentric
b : deviation from an established pattern or norm especially : odd or whimsical behavior
2a : a mathematical constant that for a given conic section is the ratio of the distances from any point of the conic section to a focus and the corresponding directrix
b : the eccentricity of an astronomical orbit used as a measure of its deviation from circularity

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Examples of eccentricity in a Sentence

Some people weren't very tolerant of his eccentricity. Talking to her plants is one of her many eccentricities.
Recent Examples on the Web Picard has flashes of eccentricity, and any science-fiction show with a Miguel de Unamuno shoutout demands a quantum of hope. Darren Franich,, "Can Star Trek: Picard recover from its bafflingly bad premiere?," 23 Jan. 2020 Symbolized by the Water Bearer, Aquarius is known for eccentricity, intellectualism, and humanitarianism. Erika W. Smith,, "This Aquarius Season, Everyone Gets Weird," 17 Jan. 2020 But the quality of eccentricity here is such that people are rather gentle and slightly unselfconscious and, oddly enough, quite unsnobby. Simon Usborne, Town & Country, "How Rumors of a Feud Between Kate Middleton and Rose Cholmondeley Captivated a Posh Corner of Britain," 5 Aug. 2019 The calculations indicated an eccentricity of 3.4, when anything much larger than about 1.2 would be considered a sign of exosolar origin. John Timmer, Ars Technica, "Comet from another Solar System looks a lot like our own," 14 Oct. 2019 Both gents are simply costumed by Tracy Dorman in nice suits, with Shorey in a flashier vest and bowtie befitting the eccentricity and poshness of his various characters. Sam Hurwitt, The Mercury News, "Review: ‘Murder for Two’ gets good and silly in Walnut Creek," 11 Sep. 2019 Tennant’s eccentricity, wit, and quick temper are much in evidence in the documentary. Tim Teeman, Town & Country, "Princess Margaret's Love Affair With the Island of Mustique," 8 Dec. 2019 The more elongated and narrow the orbit, the closer the eccentricity gets to one. Michael Greshko, National Geographic, "Bizarre comet from another star system just spotted," 12 Sep. 2019 Ashley’s eccentricities have long been a feature of Sport Direct. Washington Post, "Maverick Sports Direct Billionaire Wants an Auditor," 14 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'eccentricity.' 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 eccentricity

1545, in the meaning defined at sense 1a

History and Etymology for eccentricity

borrowed from Medieval Latin excentricitāt-, excentricitās, from ecentricus, excentricus "not having the earth exactly at its center, eccentric entry 1" + Latin -itāt-, -itās -ity

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Time Traveler for eccentricity

Time Traveler

The first known use of eccentricity was in 1545

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Statistics for eccentricity

Last Updated

20 Feb 2020

Cite this Entry

“Eccentricity.” Dictionary, Merriam-Webster, Accessed 21 Feb. 2020.

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More Definitions for eccentricity


How to pronounce eccentricity (audio)

English Language Learners Definition of eccentricity

: the quality of being strange or unusual in behavior
: an act or habit that is strange or unusual

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