Slut is a slang term used to indicate a person, (usually female, although the term is often used in the gay male community) who has, or is said to have, many sexual partners. This term is usually regarded as offensive, however it is a 'reclaimed' word with polyamorous people, in usage taken from the book The Ethical Slut.
In historical usage of English, however, the term merely meant someone untidy, and could apply to both males and females.
