idiosyncrasy

noun

id·​i·​o·​syn·​cra·​sy ˌi-dē-ə-ˈsiŋ-krə-sē How to pronounce idiosyncrasy (audio)
plural idiosyncrasies
1
a
: a peculiarity of constitution or temperament : an individualizing characteristic or quality
b
: individual hypersensitiveness (as to a drug or food)
2
: characteristic peculiarity (as of temperament)
broadly : eccentricity
idiosyncratic adjective
idiosyncratically adverb

Examples of idiosyncrasy in a Sentence

Her habit of using “like” in every sentence was just one of her idiosyncrasies. The current system has a few idiosyncrasies.
Recent Examples on the Web
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Victor then flips back to an earlier chapter, before their graduation, to a time when Agnes seems less calcified in her idiosyncrasies. Katie Walsh, Los Angeles Times, 27 June 2025 Wimbledon is widely considered one of the most prestigious of all tennis Grand Slams, known for its storied grounds, rich traditions, and unique idiosyncrasies. Jazz Tangcay, Variety, 24 June 2025 And Petrova and Trim, like many others, began to learn the sometimes cruel idiosyncrasies of the U.S. immigration system. Lauren Villagran, USA Today, 12 May 2025 But at home, my mom, creative and quirky in her own right, embraced my idiosyncrasies. Ava Xiao-Lin Rigelhaupt, HollywoodReporter, 30 Apr. 2025 See All Example Sentences for idiosyncrasy

Word History

Etymology

Greek idiosynkrasia, from idio- + synkerannynai to blend, from syn- + kerannynai to mingle, mix — more at crater

First Known Use

1604, in the meaning defined at sense 1a

Time Traveler
The first known use of idiosyncrasy was in 1604

Browse Nearby Words

Cite this Entry

“Idiosyncrasy.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/idiosyncrasy. Accessed 11 Jul. 2025.

Kids Definition

idiosyncrasy

noun
id·​io·​syn·​cra·​sy
ˌid-ē-ə-ˈsiŋ-krə-sē
plural idiosyncrasies
: a way of behaving or thinking that is characteristic of a person
idiosyncratic
ˌid-ē-ō-(ˌ)sin-ˈkrat-ik
adjective
idiosyncratically
-ˈkrat-i-k(ə-)lē
adverb

Medical Definition

idiosyncrasy

noun
id·​io·​syn·​cra·​sy ˌid-ē-ə-ˈsiŋ-krə-sē How to pronounce idiosyncrasy (audio)
plural idiosyncrasies
1
: a peculiarity of physical or mental constitution or temperament
2
: individual hypersensitiveness (as to a drug or food)
anemia accompanying the use of a sulfa drug is usually considered to be due to idiosyncrasy

More from Merriam-Webster on idiosyncrasy

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