Bisexuality (also ambisexuality) is ambiphilic orambiromantic or behavior toward males and females, usually within a gender binary context. The term is mainly used in the context of human sexual attraction to denote romantic or sexual feelings toward men and women. Pansexualityor panromantic may or may not be subsumed under bisexuality, with some sources stating that bisexuality encompasses romantic or sexual attraction to all gender identities or that it is romantic or sexual attraction to a person irrespective of that person’s biological sex or gender. Bisexuality is one of the three main classifications of sexual orientation, along with a heterosexual and a homosexualorientation, all a part of the heterosexual–homosexual continuum. People who have a distinct but not exclusive sexual preference for one sex over the other may identify themselves as bisexual.
Bisexuality has been observed in various human societies and elsewhere in the animal kingdom throughout recorded history. The term bisexuality, however, like the terms hetero- and homosexuality, was coined in the 19th century.