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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

“SNL U.K.” airs on TV network Sky and a sibling streaming service.

From The Wall Street Journal • Mar. 23, 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

Imagine being raised without a sibling and not understanding the importance of yelling “Shotgun!” at every single opportunity.

From "Far from the Tree" by Robin Benway

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.