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gender identity n.
A person's sense of being male or female, resulting from a combination of genetic and environmental influences.
an individual's self-conception as being male or female, as distinguished from actual biological sex. For most persons, gender identity and biological characteristics are the same. There are, however, circumstances in which an individual experiences little or no connection between sex and gender; in transsexualism, for example, biological sexual characteristics are distinct and unambiguous, but the affected person believes that he or she is-or ought to be-of the opposite sex (see transsexualism). Gender identity is not fixed at birth; both physiologic and social factors contribute to the early establishment of a core identity, which is modified and expanded by social factors as the child matures.