eccentricity

noun

ec·​cen·​tric·​i·​ty ˌek-(ˌ)sen-ˈtri-sə-tē How to pronounce eccentricity (audio)
plural eccentricities
Synonyms of eccentricity
1
a
: the quality or state of being eccentric
b
: deviation from an established pattern or norm
especially : odd or whimsical behavior
2
a
: 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

Synonyms of eccentricity

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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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The singers, both known for onstage personas and eccentricities, dated in 2019 and confirmed their split one year later. — Shania Russell, Entertainment Weekly, 15 June 2026 Of course, in addition to being perfect by becoming a doctor, John had selected, despite her eccentricities, the perfect mate in their parents’ eyes. — Literary Hub, 8 May 2026 Luna spends the day in the socially conscious sign of Aquarius, shifting the emotional tone toward intellect, perspective, eccentricity and detachment. — Valerie Mesa, PEOPLE, 5 June 2026 The stylistic eccentricities have been dialed back, including the use of old Hollywood film clips to reflect the action and possibly the thoughts of its main character, a cinephile from space, who is both practicing and enacting the work of a private detective. — Robert Lloyd, Los Angeles Times, 19 June 2026 See All Example Sentences for eccentricity

Word History

Etymology

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

First Known Use

1545, in the meaning defined at sense 1a

Time Traveler
The first known use of eccentricity was in 1545

Rhymes for eccentricity

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Browse Nearby Words

eccentrically
eccentricity
eccentric-shaft press
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Cite this Entry

“Eccentricity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/eccentricity. Accessed 10 Jul. 2026.

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Kids Definition

eccentricity

noun
ec·​cen·​tric·​i·​ty ˌek-ˌsen-ˈtris-ət-ē How to pronounce eccentricity (audio)
plural eccentricities
1
a
: the quality or state of being eccentric
b
: something that does not follow an established pattern, norm, or rule
especially : unusual behavior
2
: the amount by which a nearly circular path is not circular
an orbit's eccentricity

More from Merriam-Webster on eccentricity

Nglish: Translation of eccentricity for Spanish Speakers

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