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 For whatever reason, kids at school thought my eccentricity was cool. Marc Myers, WSJ, "Elizabeth Marvel Was Born With Stars in Her Eyes," 13 Oct. 2020 Because of this eccentricity, the planet is closer to us at some oppositions than others. Curtis Roelle,, "Star Points: Is the Great Pumpkin rising? No, it’s Mars," 3 Oct. 2020 However, due to the orbital eccentricity, Mars' closest approach to Earth actually happens one week earlier on Oct. 6. Curtis Roelle,, "Star Points: Is the Great Pumpkin rising? No, it’s Mars," 3 Oct. 2020 Where relationships are voluntary, let them be characterized by particularity and eccentricity. Cameron Hilditch, National Review, "Self-Interest Is Not Enough: Lincoln’s Classical Revision of the Founding," 18 Sep. 2020 The strain of speaking gently and chewing quietly and living on their guard all those years surely has something to do with the startling intensity of their emotional extremes, their obscene outbursts and streaks of eccentricity. Elaine Blair, The New York Review of Books, "Making Order of the Breakdown," 8 Sep. 2020 Expect a touch of the supernatural, malefic colleagues and plenty of eccentricity. Washington Post, "Fall reading: 12 books to keep you occupied for the rest of 2020," 5 Sep. 2020 The neatness and lack of eccentricity suggest that Phoenicians have become a passive lot, content to tend their gardens, unconcerned that their river has been diverted into most undiverting canals. Longreads, "The Ancient Waterways of Phoenix, Arizona," 10 Aug. 2020 The exhibition seeks to look beyond the persona of eccentricity that Warhol built for himself. Theresa Machemer, Smithsonian Magazine, "Take a Virtual Tour of Tate Modern’s Andy Warhol Exhibition," 9 Apr. 2020

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

19 Oct 2020

Cite this Entry

“Eccentricity.” Dictionary, Merriam-Webster, Accessed 27 Oct. 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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