I've never understood the faux outrage from some gays and lesbians about the word "cisgender." They claim it's a new derogatory term that transgender people have come up with to refer to non-transgender people. It never appears to enter their minds that just like most words in the English language, there's another word to describe the exact opposite of a different label. Saying "cis" is offensive is like saying "straight" is derogatory compared to "not gay."
So for those who insist this is a new term that trans people have come up with on their own, I give you Cristan Williams' history lesson from Transadvocate. Can we stop flogging that poor dead horse now?