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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

  • half-sibling noun

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.

Keep Reading on Vocabulary.com

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.

But Jamie has never shown any jealousy towards his younger sibling, and their mutual affection has often been in evidence.

From BBC • Apr. 15, 2026

Like its IL-23 sibling, Oruka’s IL-17 drug should allow less-frequent dosing than marketed products.

From Barron's • Apr. 10, 2026

My sibling said she felt crestfallen and likened it to discovering there was no Santa Claus.

From Los Angeles Times • Apr. 7, 2026

My sibling and I want to inherit the house one day, but we might have to sell to pay off the debt.

From The Wall Street Journal • Apr. 6, 2026

His mother had already passed away years earlier, and his sister, his only other sibling, lived far away.

From "The Gene" by Siddhartha Mukherjee