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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

  1. 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

Etymology

Origin of sibling

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

Explanation

A sibling is your brother or sister. It's that simple. The word sibling once meant anyone who is related to you, but now it's reserved for children of the same parent or parents. It is a word that was once out of use but then brought back into English in the early 1900s as a useful word in anthropology. If you and your brother fight all of the time, your parents might call it sibling rivalry. You might just call him annoying and run from the room.

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Vocabulary lists containing sibling

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.

Sibling relationships don’t develop in a straight line.

From MarketWatch • Nov. 27, 2025

Appeared in the October 17, 2025, print edition as 'Adult Swim’s Sly Sibling Comedy'.

From The Wall Street Journal • Oct. 16, 2025

"Sibling love is something unique, you can't choose your siblings. It can be complicated, it takes work, but when it's strong, I believe it's one of the most powerful bonds there is," he added.

From BBC • May 24, 2025

Sibling studies account for these confounding factors because siblings are exposed to similar environments.

From Scientific American • May 21, 2023

Sibling Treachery Closer to home, Cleopatra needed to be on guard for ruthless enemies within her own family.

From "Sterling Biographies®: Cleopatra: Egypt's Last and Greatest Queen" by Susan Blackaby

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