Sigourney Weaver, (born Susan Alexandra Weaver on October 8, 1949 in New York, New York) is an American actress perhaps best known for her portrayal of Ripley in Alien (1979) and its sequels. Weaver is also notable for her stature, standing 5 ft 11½ in tall.

Susan began using the name Sigourney Weaver in 1963, after a character in F. Scott Fitzgerald's The Great Gatsby. She attended high school in New York City with fellow-actress Meryl Streep. During the 1970s, Weaver studied English at Stanford University and then drama at Yale, where she appeared in original plays by friend and classmate, Christopher Durang.

Her part in Ridley Scott's 1979 film Alien as the sole survivor, Lieutenant Ellen Ripley, ensured her role in the sequels Aliens, Alien³ and Alien: Resurrection. She was nominated for a Best Actress Academy Award for portraying Ripley in Aliens. Many of her roles since have been in knowing reference to the tough character of Ripley. Also another well known character she played was Dana Barrett in Ghostbusters and Ghostbusters II.

It is also notable that she is one of the ten thespians to receive two Academy Award nominations in the same year. Weaver received a Best Actress nomination for her role as gorilla obsessed Dian Fossey in Gorillas in the Mist and a Best Supporting Actress nomination for her role as the bitchy trustfund baby Katharine Parker (who gets her comeuppance) in Working Girl, opposite Harrison Ford and Melanie Griffith. She did not win either one, but she did win a Golden Globe for each role, respectively.

She is the daughter of the late NBC television executive Pat Weaver, and his wife, Elizabeth. She is also a niece of comedian and actor, Doodles Weaver. Since 1984 she has been married to theater director Jim Simpson (of The Flea Theater), and has one child, Charlotte Simpson (born 1990).