related by blood; akin.


a kinsman; relative.
one's kin or kindred.
Anthropology. a unilateral descent group.

Origin of sib

before 900; Middle English sib(e), sibb(e), Old English sib(b) (orig. adj.); cognate with Old Norse sifjar (plural) relatives, Old Frisian sib (adj.), sibba (noun), Middle Dutch sibbe (noun and adj.), German Sippe kin; cf. gossip Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for sib

Historical Examples of sib

  • Madame, is he sib to him that aided in the slaughter of Eastern's Eve night?'

    Two Penniless Princesses

    Charlotte M. Yonge

  • He had had letters from him that told how they were sib and rib.

  • Ye're ower het and ower fu', sib to some o' the laird's tenants.

    The Proverbs of Scotland

    Alexander Hislop

  • If you can't find a pet name for me you may call me Sibylla, or Sibyl, or just Sib.

    The Tigress

    Anne Warner

  • The earth is drunk with sweetness, and I see now how great joy is sib to great pain!


    Mary Johnston

British Dictionary definitions for sib



a blood relative
a brother or sister; sibling
kinsmen collectively; kindred
any social unit that is bonded by kinship through one line of descent only

Word Origin for sib

Old English sibb; related to Old Norse sifjar relatives, Old High German sippa kinship, Latin suus one's own; see gossip


abbreviation for (in Britain)

(the former) Securities and Investments Board
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

Word Origin and History for sib

short for sibling, attested from 1957.

Online Etymology Dictionary, © 2010 Douglas Harper

sib in Medicine




A blood relation; a relative.
A person's relatives when considered as a group; kinfolk.
A brother or sister; a sibling.


Related by blood; kindred.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.