Many gender systems around the world include three or more genders, deriving the concept either from the traditional, historical recognition of such individuals or from its modern development in the lgbtq community, which can include third gender. “third gender” is used to describe some people whose gender identity is different than the sex they were assigned at birth (e.g Third sex the term third sex originated in the late nineteenth century among sexologists as a way to describe homosexual men and lesbians
Number 3 3d Png - vrogue.co
It did not carry the moral or legal stigma of sodomite, and suggested an innate or biological factor existed in behaviors that fell outside traditional categories of male and female
So in short, there is no biological third sex, but that doesn't mean you can always categorize a person as biologically male or female
As you quoted, the hijira are usually physiologically male but have a different gender identity. A category of people whose gender doesn't fit within the limiting and inaccurate notion of a gender binary within a particular culture