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 of eccentricity

• characteristic
• trick
• trait
• idiosyncrasy
• mannerism
• quirk
• singularity
• peculiarity
• individualism
• curiosity
• oddity
• habit
• twist
• tic

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

Outkast made their eccentricities feel normal, setting the bar for rap-song experimentation in the stratosphere. —New York Times, 28 Apr. 2026

Screenwriter Craig Mazin finds a way, however, by smartly retooling Swann’s story for a younger audience, stripping out the text’s more violent eccentricities, while preserving the universally winning curiosity of the premise. —Guy Lodge, Variety, 27 Apr. 2026

The album is full of strange, brilliant contradictions; Oklou slides masterfully between fun and eccentricity, pump and pathos. —Sheldon Pearce, New Yorker, 24 Apr. 2026

His process was marked by a certain eccentricity that differentiated his art from a lot of similar work. —Alex Greenberger, ARTnews.com, 20 Apr. 2026

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

Rhymes for eccentricity

• authenticity
• chromaticity
• concentricity
• domesticity
• elasticity
• electricity
• iconicity
• metallicity
• multiplicity
• specificity
• synchronicity
• analyticity

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