The typical definition is the one defined in this article: "the socially constructed roles, behaviors, activities, and attributes that a given society considers appropriate for boys and men or girls and women." But if this is true, then gender seems like a rather trivial and fickle thing. If a man wants to be a woman, does that merely mean that he wants to be a person who can wear dresses, makeup and wigs? Are these things the essence of womanhood? If not, then what is? Perhaps what is really at issue here is the fact that our societies have built up rigid gender roles that make people feel uncomfortable taking on roles or behaviors traditionally only exhibited by the opposite gender. The alienation that a person feels might not be related to his sexual identity, per se, but rather the social stigma of aligning with unconventional gender roles. I think the reason I'm having trouble grasping this is because I don't really consider my gender or my sex to be huge parts of my identity. In my mind, I am not "John the male" but rather "John the person."