A dyke (homosexual woman, lesbian, queer woman) who does kink or BDSM with other women. So named because of the very common leather sexual fetish (similar to same in the gay men's leather community) that exists in the women's queer/kink community.
The term leatherdyke applies equally to tops, bottoms, and switches.
One need not own or wear leather to self-identify as a leatherdyke. But it helps.
I had a date with a leatherdyke last night, and she spanked me. I think I liked it.