from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun One of two or more individuals having one or both parents in common; a brother or sister.

from The Century Dictionary.

  • noun A member of a family born to the same parents; a brother or a sister considered without reference to sex.

from the GNU version of the Collaborative International Dictionary of English.

  • adjective of or pertaining to a sibling, n.
  • noun a brother or a sister.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun A person who shares same parents. One's brother or sister.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a person's brother or sister


from The American Heritage® Dictionary of the English Language, 4th Edition

[Middle English, from Old English, from sibb, kinsman; see sib.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

1903, modern revival of Old English sibling ("relative, a relation, kinsman"), equivalent to sib +‎ -ling. Compare Middle English sib, sibbe ("relative, kinsman"). The term apparently meant merely kin or relative until the 20th century when its necessity for the study of genetics led to its broader use. For example, the OED has a 1903 citation in which "sibling" must be defined for those who don't know the intended meaning.


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  • A very useful word and one that seems to be making a comeback. It works especially well with an adjectival function (sibling jealousy/rivalry). A bit unusual in the plural ("I have three siblings") where the speaker seems to be trying to hide something. Other European languages deal with this in different ways: in Italian your brothers and sisters are all "fratelli" (male gender still dominates) but in German they are "Geschwister" which sounds more feminine.

    January 8, 2008

  • Also used in sibling species.

    January 8, 2008