Transvestite: A man who wears women's clothes and make-up, and still has his cock and balls.

Transsexual: A man who has had his cock and balls chopped off and replaced with a surgical pussy and fake tits.

Pre-Op Transsexual: This is often confused with the above, but they are very different. A Pre-Op Transsexual still has his cock and balls, although he may have fake tits.

Thank you.

LB.

Couldn't a pre-op have real tits due to estrogen shots?

Yes, but they are still Pre-Op. They only become FULL transsexuals when they gets their cock and balls sliced off. Simple.
TS.

With a title like "correct definitions..." I guess this would be a good string for me to ask a fairly stupid question - though it isn't tranny-related. Would someone explain the term "bukkake" to me? I know it has something to do with vast amounts of cum, facials, asian chicks (I guess), but I see it's become a major, distinct genre and was curious how the term, um... came about. Thanks.

A 'BUK' is an ancient Japanese expression meaning 'many'.
'KAKE' is an old Chinese expression meaning "he who has good time'.
Hence Bukkake.
TS.