sibling
Americannoun
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a brother or sister.
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Anthropology. a comember of a sib, a unilateral descent group thought to share kinship through a common ancestor.
adjective
noun
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a person's brother or sister
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( as modifier )
sibling rivalry
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any fellow member of a sib
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.
Vocabulary lists containing sibling
It's All in the Family
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Unit 3: Compelling Evidence
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Unit 2: Pivotal Words and Phrases
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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.
Because it progresses more gradually, donor immune cells have time to gain control, especially with a sibling donor who matched me so closely.
From The Wall Street Journal • Apr. 19, 2026
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
We have all sorts of questions about how to help her get out of this, because my sibling and I want to inherit the house and share it.
From MarketWatch • Apr. 6, 2026
It was suggested that he start sessions with a cat psychiatrist to work out what the doctor called a case of sibling rivalry with Bunnicula.
From "Bunnicula" by Deborah Howe and James Howe
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.
