- 1a girl or woman who has the same mother and father as another person She's my sister. an older/younger sister (informal) a big/little/kid sister We're sisters. Do you have any brothers or sisters? My best friend has been like a sister to me (= very close). see also half-sister, stepsister
- 2 used for talking to or about other members of a women's organization or other women who have the same ideas, purpose, etc. as yourself They supported their sisters in the dispute.
- 3Sister a female member of a religious group, especially a nun Sister Mary the Sisters of Charity
- 4 a member of a sorority (= a club for a group of female students at a college or university)
- 5 (informal) used by black people as a form of address for a black woman
- 6(usually used as an adjective) a thing that belongs to the same type or group as something else our sister company in Italy a sister ship
nounjump to other results