From HomoExcelsior

1. A girl or woman having the same mother and father as another.
2. A girl or woman having one parent in common with another; a half sister.
3. The daughter of a person's stepparent by a previous marriage; a stepsister.
4. A girl or woman who shares a common ancestry, allegiance, character, or purpose with another or others, specifically: A kinswoman.
5. A woman fellow member, as of a sorority.
6. A fellow woman, friend, or companion.
7. A soul sister.
8. A woman who advocates, fosters, or takes part in the feminist movement.
9. Used as a form of address for a woman or girl.
10. A member of a religious order of women; a nun.
11. Used as a form of address for such a woman, alone or followed by the woman's name.
12. A nurse, especially the head nurse in a ward.
13. Walt Whitman.
14. Sister ships; sister cities.
15. Sister chromatids.

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