It's an adjective, not used much.
Without the "e", lesbisch, is used much more, and lesbienne also much more common. But we couldn't say how much type in trafic you could receive in the future..
Back in October '06, I also looked at 'lesbische' for Lesbian in German, but after a quick research realised this was not a gem at all - Just be careful with some of those online Translation Sites including Google - they can be very misleading for many words indeed.