Cisgender (derived from cis- "on the same side" + gender), is a descriptive term meaning "having a gender which matches (is on the same side as) one's apparent (or assigned) gender at birth"; it is the antonym for transgender. It appears to have originated in academic journals in the 1990s, and began to gain popularity when it was used by transgender theorist Julia Serano discussed it in her 2007 book Whipping Girl. It was added to the Oxford English Dictionary in 2015.
- 2015-11-07 How we ended up 'cisgender': The history of a tendentious word (archive.org)
- 2014-05-01 Cisgender, Transgender Studies Quarterly vol.1 issue 1-2: "“Cisgender,” when used appropriately, helps distinguish diverse sex/gender identities without reproducing unstated norms associated with cisness. For example, instead of simply saying "man" or "woman," one would use "cis woman" or "trans man" in much the same way one would use "black woman" or "white man" (Stryker 2008). Finally, as a substitute for “nontransgender,” “cisgender” can be viewed as a way of including transgender as a categorical equal in the complex way we identify as sexed and gendered human beings."
- whatdoescismean.com: suggests a particular paper where the term may have first been used