I also call it SRS... sex reassignment surgery. I think that's a bit more accurate to what it is doing rather than "gender reassignment." Gender refers to the social construct. It refers to our society and how it classifies people. Sex, on the other hand, usually refers to one's physical body and reproductive functions.
Socially transitioning is really the "gender reassignment" part of it, because that is where people change from categorizing you within one social construct to the other social construct. Whereas the surgery is completely an altercation to your physical sex. One can have a gender reassignment while never doing a single thing to sexually transition.
And I definitely prefer "sex reassignment" to "sex change" because the word "reassignment" is much more gentle, and implies that the reason for it was an improper assignment in the first place, rather than the blunt "I'm switching it, and this is the sole thing that's doing it" mentality that the term "sex change" implies. And this is a big problem. The general public is still learning that the surgery isn't the only thing that makes someone transsexual. The term "sex change" preserves this notion, because it implies that the surgery is the only thing that people do in order to change their physical sex, which opens the door for discrimination based on our surgical status.
(Granted, among trans friends, I just refer to it as "the surgery," because they immediately know what I'm talking about. Or "getting girl parts.")
