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Synonyms

singleton

American  
[sing-guhl-tuhn] / ˈsɪŋ gəl tən /

noun

  1. a person or thing occurring singly, especially an individual set apart from others.

    1. a child or animal that is the only one born at one birth.

      a research program involving twins and singletons.

    2. an only child in a family.

  3. Chiefly British. an unmarried person; a single.

  4. Cards. a card that is the only one of a suit in a hand.

  5. Mathematics. a set consisting of one given element.

singleton British  
/ ˈsɪŋɡəltən /

noun

  1. bridge an original holding of one card only in a suit

  2. a single object, individual, etc, separated or distinguished from a pair or group

  3. maths a set containing only one member

  4. a person who is neither married nor in a relationship

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of singleton

First recorded in 1875–80; single + -ton

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Dennis is indeed twinless — not by a twist of fate but because he came into this world a singleton and is lying.

From Los Angeles Times • Sep. 5, 2025

Bring on the granny pants and awkward moments, because beloved singleton Bridget Jones is back on our screens on Thursday.

From BBC • Feb. 9, 2025

The study included singleton pregnancies that delivered between 2008 and 2015.

From Science Daily • Mar. 28, 2024

“I’m the singleton of the family and the friend group,” said the 53-year-old Plessis, who lives in Manitoba, Canada.

From Seattle Times • Feb. 9, 2024

Old Hickory looks sort of puzzled; but he forks out the singleton, and the messenger climbs in after it.

From Torchy, Private Sec. by Lincoln, F. Foster

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.