eccentricity

noun

ec·​cen·​tric·​i·​ty ˌek-(ˌ)sen-ˈtri-sə-tē 

plural eccentricities

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

• crotchet
• curiosity
• erraticism
• idiosyncrasy
• individualism
• kink
• mannerism
• oddity
• peculiarity
• quiddity
• quip
• quirk
• singularity
• tic
• trick
• twist

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

Through flood, earthquake, and subsidence, the Goose was coddled like a pedigree bird at a cost of US$1 million a year until Hughes died in 1976 after years of decline into Las Vegas penthouse seclusion and bizarre eccentricity. —David Szondy, New Atlas, 25 Dec. 2024

The Parker's dedication to eccentricity runs deep, even down to the bathroom amenities. —Catherine Garcia, theweek, 20 Dec. 2024

Earth's orbital eccentricity is 0.017; Mars' is 0.055, and Mercury's is 0.206. —Keith Cooper, Space.com, 28 Jan. 2025

Indeed, for all his film’s eccentricities — Blue Velvet’s freaky Frank Booth huffing, well, whatever that stuff is, Lost Highway’s spine-chilling Mystery Man, or Wild at Heart’s Sailor kung fu-kicking in a snakeskin jacket — Lynch wasn’t trying to be controversial. —Damon Wise, Deadline, 17 Jan. 2025

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

Kids Definition

eccentricity

noun

ec·​cen·​tric·​i·​ty ˌek-ˌsen-ˈtris-ət-ē 

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