"Cisgender"? Not so much.

Of course, there's more at stake in the viability of "cisgender" than mere words. "Cisgender" suggests a commonality among transgender and non-transgender people, at a time when transgender people are struggling for recognition. It tells us that we all experience some kind of relationship between our bodies and our selves, whatever that relationship may be. And it reminds us that those who experience a "match" between their body and their selves have it a lot easier in our society than those who do not. To the extent that "cisgender" helps raise awareness of intolerance and injustice towards transgender people, it serves a crucial political purpose right now. Potentially, "cisgender" could help build consensus on transgender rights.

However, the politics of "cisgender" have already proven divisive. Perhaps the most surprising protests are coming from the left—from people, that is, who might otherwise be counted on to support the transgender movement. There are feminists who balk at the idea that cisgender women are privileged in relation to transgender women, who were born male. Among other potential benefits, such as "passing" as men in a patriarchal culture, transgender women don't have to worry about reproductive rights. The Huffington Post recently collected a grab-bag of very mixed reactions to "cisgender" from the gay community. It's clear that some gay men and lesbians see "cisgender" as a slur, a way of labeling them as elitists or conformists after all (i.e., as not "queer" enough). Some think "cisgender" validates the notion that there are two (and only two) genders, correlating with two (and only two) sexes, just as many are exploring non-binary gender identities, such as "genderqueer."

All of which brings us back to the problem of the word "cisgender" itself. Linguists agree that the survival of a neologism relies, above all, on whether it names a stable and coherent concept, an idea that will last. It's the uncertainty of the concept behind the word "cisgender," for now, that really hints at trouble.

As the social and medical sciences tell us more and more about ourselves and one another, we may eventually settle on the right words, the true words or, at least, the ones that reflect the data. "Cisgender" may or may not end up being one of them. But maybe, in the long run, it doesn't matter. Maybe the impact of Facebook's 56 genders will one day prove to have had nothing to do with naming all the possibilities for gender identity, but rather with helping to make the idea of possibility, itself, official. Our vocabulary of gender and sex is in flux right now because our ideas about gender and sex are in flux, too.

So will "cisgender" be an upcoming "Word of the Year," the linguistic sign of our times? Or will we just forget about it?

Quite possibly, both.

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