idiosyncrasy

American  

[id-ee-uh-sing-kruh-see, -sin-] / ˌɪd i əˈsɪŋ krə si, -ˈsɪn- /

noun

plural

idiosyncrasies

1. a characteristic, habit, mannerism, or the like, that is peculiar to an individual.

   Synonyms:

   quirk, peculiarity

2. the physical constitution peculiar to an individual.

3. a peculiarity of the physical or the mental constitution, especially susceptibility toward drugs, food, etc.

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idiosyncrasy British  

/ ˌɪdɪəʊˈsɪŋkrəsɪ /

noun

1. a tendency, type of behaviour, mannerism, etc, of a specific person; quirk

2. the composite physical or psychological make-up of a specific person

3. an abnormal reaction of an individual to specific foods, drugs, or other agents

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Related Words

See eccentricity.

Other Word Forms

• idiosyncratic adjective

Etymology

Origin of idiosyncrasy

First recorded in 1595–1605; from Greek idiosynkrāsía, equivalent to idio- idio- + syn- syn- + krâs(is) “a blending” + -ia -y ³

Explanation

If a person has an idiosyncrasy, he or she has a little quirk, or a funny behavior, that makes him or her different. If you only say goodbye in French, never in English, that would be an idiosyncrasy. Idio seems like it means stupid, but really it is Latin for "one's own," as an idiosyncrasy is one's own particular, usually odd, behavior. Putting salt in your hot chocolate or needing the light on to sleep or tapping your head while you think are all idiosyncrasies. A machine such as a DVD player has an idiosyncrasy if you have to do something weird to it to make it work like having to bang it on the back left-hand side to stop it from skipping.

Example Sentences

Indeed, the very features that make gifts inefficient as market transactions—surprise, idiosyncrasy, miscalibration—are often what make them meaningful as social gestures.

From The Wall Street Journal • Dec. 23, 2025

The headline proposal of the reforms is the removal of the not proven verdict - a legal idiosyncrasy that can be traced back to the 17th Century.

From BBC • Sep. 15, 2025

And “country,” the hands-down favorite music of “real Americans,” has long been a production-line item with as much idiosyncrasy in the songs as Olive Garden breadsticks.

From Salon • Aug. 9, 2025

We may not be artists, but we can live like we are: We can remember that idiosyncrasy, and our unabashed embrace of it, is the true way to live well.

From New York Times • Mar. 18, 2024

The results never completely caught on—but they endure as a historical curiosity of some idiosyncrasy.

From "Words Like Loaded Pistols" by Sam Leith

Related Words

• eccentricity
• mannerism
• peculiarity
• trait