cis-

Meanings

1. On this side of.
2. Forming names of chemical compounds in which two atoms or groups are situated on the same side of some plane of symmetry passing through the compound.
3. Not trans.
4. Being, or pertaining to being, cis.

Etymology

From the Latin preposition cis (“on this side of”). The earliest known sexuality-related use of the prefix in any language was in a 1914 German-language book on sexology. According to the Oxford English Dictionary, the earliest use of the prefix in the context of gender in English dates from 1994.