Bisexuality is a romantic or sexual attraction or behavior toward both males and females , [ 1 ] [ 2 ] [ 3 ] to more than one gender , [ 4 ] or to both people of the same gender and different genders. The term bisexuality is mainly used for people that have both heterosexual and homosexual attraction.
A bisexual identity does not necessarily equate to equal sexual attraction to both sexes; commonly, people who have a distinct but not exclusive sexual preference for one sex over the other also identify themselves as bisexual. Scientists do not know the exact determinants of sexual orientation, but they theorize that it is caused by a complex interplay of genetic , hormonal , and environmental influences , [ 11 ] [ 12 ] [ 13 ] and do not view it as a choice.
Bisexuality has been observed in various human societies, [ 16 ] as well as elsewhere in the animal kingdom, [ 17 ] [ 18 ] [ 19 ] throughout recorded history. The term bisexuality , like the terms hetero- and homosexuality , was coined in the 19th century by Charles Gilbert Chaddock. Bisexuality is variously defined as romantic or sexual attraction to both males and females, [ 1 ] [ 2 ] [ 3 ] to more than one gender, [ 22 ] or attraction to both people of the same gender and different genders.
In other words, someone does not have to be exclusively homosexual or heterosexual, but can feel varying degrees of both. Sexual orientation develops across a person's lifetimeβdifferent people realize at different points in their lives that they are heterosexual, bisexual or homosexual. Sexual attraction, behavior, and identity may also be incongruent, as sexual attraction or behavior may not necessarily be consistent with identity.
Some individuals identify themselves as heterosexual, homosexual, or bisexual without having had any sexual experience. Others have had homosexual experiences but do not consider themselves to be gay, lesbian, or bisexual. Some sources state 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, equating it to or rendering it interchangeable with pansexuality.
