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

  • noun A female having the same parents as another or one parent in common with another.
  • noun A girl or woman who shares a common ancestry, allegiance, character, or purpose with another or others, specifically.
  • noun A kinswoman.
  • noun A woman fellow member, as of a sorority.
  • noun A fellow woman.
  • noun A close woman friend or companion.
  • noun A fellow African-American woman or girl.
  • noun A woman who advocates, fosters, or takes part in the feminist movement.
  • noun Informal Used as a form of address for a woman or girl.
  • noun A member of a religious order of women; a nun.
  • noun Used as a form of address for such a woman, alone or followed by the woman's name.
  • noun Chiefly British A nurse, especially the head nurse in a ward.
  • noun One identified as female and closely related to another.
  • adjective Related by or as if by sisterhood; closely related.
  • adjective Genetics Of or being one of an identical, related, or homologous pair.

from The Century Dictionary.

  • noun A female person in her relation to other children born of the same parents; a female relative in the first degree of descent or mutual kinship; also, a female who has attained a corresponding relation to a family by marriage or adoption: correlative to brother; often used as a term of endearment.
  • noun Metaphorically, a woman of one's own faith, church, or other religious community.
  • noun In the Roman Catholic and some other churches, a member of a religious community or order of women; a woman who devotes herself to religious work as a vocation: as, sisters of mercy. See sisterhood, 2.
  • noun That which is allied by resemblance or corresponds in some way to another or others, and is viewed as of feminine rather than masculine character.
  • Standing in the relation of a sister, whether by birth, marriage, adoption, association, or resemblance; akin in any manner; related.
  • To be a sister or as a sister to; resemble closely.
  • To address or treat as a sister.
  • To be a sister or as a sister; be allied or contiguous.

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

  • transitive verb obsolete To be sister to; to resemble closely.
  • noun A female who has the same parents with another person, or who has one of them only. In the latter case, she is more definitely called a half sister. The correlative of brother.
  • noun A woman who is closely allied to, or assocciated with, another person, as in the sdame faith, society, order, or community.
  • noun One of the same kind, or of the same condition; -- generally used adjectively.
  • noun (Naut.) a tackle block having two sheaves, one above the other.
  • noun a pair of hooks fitted together, the shank of one forming a mousing for the other; -- called also match hook.
  • noun (R. C. Ch.) See under Charity, and Mercy.

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

  • noun a daughter of the same parents as another person; a female sibling.
  • noun a female member of a religious community; a nun.
  • noun UK a senior or supervisory nurse, often in a hospital.
  • noun any woman or girl with whom a bond is felt through common membership of a race, profession, religion or organization, such as feminism.
  • noun slang a black woman
  • noun informal a form of address to a woman
  • noun a woman, in certain labour or socialist circles; also as a form of address.
  • noun attributively Of or relating to an entity that has a special or affectionate, non-hierachical relationship with another.
  • noun In the same class.
  • verb transitive, construction To strengthen (a supporting beam) by fastening a second beam alongside it.
  • verb obsolete, transitive To be sister to; to resemble closely.

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

  • noun (slang) sometimes used as a term of address for attractive young women
  • noun a female person who is a fellow member of a sorority or labor union or other group
  • noun (Roman Catholic Church) a title given to a nun (and used as a form of address)
  • noun a female person who has the same parents as another person


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

[Middle English, from Old Norse systir; see swesor- in Indo-European roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Middle English sister, suster, partly from Old Norse systir ("sister") and partly from Old English swustor, sweoster, sweostor ("sister, nun"); both from Proto-Germanic *swestēr (“sister”), from Proto-Indo-European *swésōr (“sister”). Cognate with Scots sister, syster ("sister"), West Frisian sus, suster ("sister"), Dutch zuster ("sister"), German Schwester ("sister"), Swedish syster ("sister"), Icelandic systir ("sister"), Gothic 𐍃𐍅𐌴𐍃𐍄𐌰𐍂 (swestar, "sister"), Latin soror ("sister"), Russian сестра (sestra, "sister"), Lithuanian sesuo ("sister"), Albanian vajzë ("girl,maiden"), Sanskrit स्वसृ (svásṛ, "sister").


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  • "Sister I see you

    Dancing on the stage

    Of memory

    Sister I miss you

    Entwined, you and I

    Our souls speak from across the miles

    Intertwined, you and I

    Our blood flows from the same inside

    Half of me, breathes in you

    Thoughts of love remain true"

    January 2, 2007