[ sis ]

  1. cisgender or cissexual: He may not be macho, but he's definitely a cis male.

  1. a person who is cisgender or cissexual.

Origin of cis

By shortening

usage note For cis

See trans, gender1.

Other definitions for cis- (2 of 3)


  1. a prefix occurring in loanwords from Latin meaning “on the near side of; on this side of” (cisalpine); on this model, used in the formation of compound words (cisatlantic).

  2. Chemistry. a specialization of this denoting a geometric isomer having a pair of identical atoms or groups attached on the same side of two atoms linked by a double bond.: Compare trans- (def. 2).

  1. a prefix meaning “on the same side of,” referring to the alignment of one’s gender identity with one’s sex assigned at birth (cisgender; cissexual).

Origin of cis-

From Latin cis (adverb and preposition) “on this side, on this side of, within”

Other definitions for C.I.S. (3 of 3)


  1. Commonwealth of Independent States. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

British Dictionary definitions for CIS (1 of 2)


abbreviation for
  1. Commonwealth of Independent States

British Dictionary definitions for cis- (2 of 2)


  1. on this or the near side of: cisalpine

  2. (often in italics) indicating that two groups of atoms in an unsaturated compound lie on the same side of a double bond: cis- butadiene Compare trans- (def. 5)

Origin of cis-

from Latin

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012