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Synonyms

sibling

American  
[sib-ling] / ˈsɪb lɪŋ /

noun

  1. a brother or sister.

  2. Anthropology. a comember of a sib, a unilateral descent group thought to share kinship through a common ancestor.

adjective

  1. of or relating to a brother or sister.

    sibling rivalry.
sibling British  
/ ˈsɪblɪŋ /

noun

    1. a person's brother or sister

    2. ( as modifier )

      sibling rivalry

  2. any fellow member of a sib

"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

Other Word Forms

  • half-sibling noun

Etymology

Origin of sibling

before 1000; late Middle English: relative, Old English; sib, -ling 1

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.

That risk increases to 10 percent if a parent or sibling is affected, and rises to 50 percent for identical twins.

From Science Daily • Apr. 3, 2026

Harrison says sibling spats were the least of the pair's worries as they took on the voyage.

From BBC • Apr. 3, 2026

Another sibling in the family, Ethan, is an El Camino Real graduate pitching at Oakland University.

From Los Angeles Times • Mar. 26, 2026

My brother, who is the eldest sibling, and I are the only surviving members of our family since our parents passed away.

From MarketWatch • Mar. 21, 2026

I think of the rare jackpot nights when I ended the day at a sleepover or sharing the room with a sibling or a friend I genuinely liked.

From "Every Day" by David Levithan

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.