What are the definitions of sexualities?

[Tungsten]

In regards to the definition of the various sexualities, in your opinions would you say they are based on biological sex, or on gender? I am just curious to what you all think :)

[man with freaky plan]

In my experience it is a bit of both, but that is not always the case, for instance there are people who are bi, but are only attracted to feminine men, and there are people who are straight, who are attracted to very masculine woman.
Honestly I've always considered the concept of gender to be broken, it makes very little sense to me, so I'd point sexuality to sex.

[Karkat]

Sexuality almost entirely has to do with sex- as you're attracted to the opposite SEX if you're heterosexual.

However, with the inclusion of the trans* community, it's a little complicated.