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 the divination trial, the audience learns that much of Lilia’s eccentricity comes from her experience living life out of order, giving more context to moments earlier in the season, where the character would blurt out what seemed to be random statements. —Marcus Jones, IndieWire, 12 May 2025

Lyonne forged a career by finding and later creating projects that capitalized on her undeniably intrepid personality, wrapping the roles around her eccentricities rather than conforming to what was expected of a female performer in Hollywood. —Lorraine Ali, Los Angeles Times, 8 May 2025

The staff members are caught in the crossfire, forced to navigate the guests' eccentricities and escalating conflicts. —Martine Paris, Forbes, 20 Mar. 2025

In the mornings, Pauline would take beach walks, a picture of eccentricity in huge, bright satin duchess Balenciaga coats over matching capri pants and slippers. —Ralph Rucci, Robb Report, 20 Apr. 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

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