Cis is a term used to describe a person whose gender identity corresponds to their sex assigned at birth. The word cisgender is the antonym of transgender. The prefix cis- is Latin and means "on this side of". The term cisgender was coined in 1994 and entered into dictionaries starting in 2015 as a result of changes in social discourse about gender. Related concepts are cisnormativity (the presumption that cisgender identity is preferred or normal) and cissexism (bias or prejudice favoring cisgender people) . The word cis exists to fill a gap that would otherwise exist in language, and that has previously been filled with words like "normal" or "regular," which position trans people as "abnormal" or "irregular" as a result.