Homosexual transsexual is a taxonomic category of transsexual individuals used in sexology, psychology, and psychiatry. It categorizes trans women who are exclusively attracted to men, and less often trans men who are exclusively attracted to women, based on their sex assigned at birth, rather than their current gender identity. The concept of categorizing trans women by sexual orientation originated with Magnus Hirschfeld in 1923, and was further developed by the sexologist Harry Benjamin in 1966 as a component of the Benjamin scale. The specific term "homosexual transsexual" was coined by Kurt Freund in 1973, and used from 1982 onward by him and others.