sister

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A female having the same parents as another or one parent in common with another.
2. n. A girl or woman who shares a common ancestry, allegiance, character, or purpose with another or others, specifically:
3. n. A kinswoman.
4. n. A woman fellow member, as of a sorority.
5. n. A fellow woman.
6. n. A close woman friend or companion.
7. n. A fellow African-American woman or girl.
8. n. A woman who advocates, fosters, or takes part in the feminist movement.
9. n. Informal Used as a form of address for a woman or girl.
10. n. Ecclesiastical A member of a religious order of women; a nun.
11. n. Ecclesiastical Used as a form of address for such a woman, alone or followed by the woman's name.
12. n. Chiefly British A nurse, especially the head nurse in a ward.
13. n. One identified as female and closely related to another: "the sisters Death and Night” ( Walt Whitman).
14. adj. Related by or as if by sisterhood; closely related: sister ships; sister cities.
15. adj. Genetics Of or being one of an identical pair: sister chromatids.

Century Dictionary and Cyclopedia

1. n. 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.
2. n. Metaphorically, a woman of one's own faith, church, or other religious community.
3. n. 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.
4. n. 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.
5. Standing in the relation of a sister, whether by birth, marriage, adoption, association, or resemblance; akin in any manner; related.
6. To be a sister or as a sister to; resemble closely.
7. To address or treat as a sister.
8. To be a sister or as a sister; be allied or contiguous.

Wiktionary

1. n. a daughter of the same parents as another person; a female sibling.
2. n. a female member of a religious community; a nun.
3. n. a senior or supervisory nurse, often in a hospital.
4. n. any woman or girl with whom a bond is felt through common membership of a race, profession, religion or organization, such as feminism.
5. n. a black woman
6. n. a form of address to a woman
7. n. Of or relating to an entity that has a special or affectionate relationship with another
8. v. To strengthen (a supporting beam) by fastening a second beam alongside it.

GNU Webster's 1913

1. n. 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.
2. n. A woman who is closely allied to, or assocciated with, another person, as in the sdame faith, society, order, or community.
3. n. One of the same kind, or of the same condition; -- generally used adjectively.
4. v. To be sister to; to resemble closely.

WordNet 3.0

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