Gender identity is one's personal experience of one's own gender. It is separate from their assigned sex and appearance. Because gender identity is an internal experience, it cannot be assigned, diagnosed, measured or disproved by anyone else - a person's gender identity is their own.
Every person thinks of their own gender slightly differently, but there are a common set of labels that most people find helpful in communicating their identity to others. These gender identity labels include man, woman, cisgender, transgender, and non-binary. Pressuring someone into a label they do not relate to can result in dysphoria.
Gender identity was originally a medical term used to explain sex reassignment surgery to the public, but is also found in psychology, often as core gender identity. Although the formation of gender identity is not completely understood, many factors have been suggested as influencing its development. Biological factors that may influence gender identity include pre- and post-natal hormone levels and gene regulation. Social factors which may influence gender identity include gender messages conveyed by family, mass media, and other institutions. In some cases, a person's gender identity may be inconsistent with their biological sex characteristics, resulting in individuals dressing and/or behaving in a way which is perceived by others as being outside cultural gender norms; these gender expressions may be described as gender variant or transgender.
- "The term 'gender identity' was used in a press release, November 21, 1966, to announce the new clinic for transsexuals at The Johns Hopkins Hospital. It was disseminated in the media worldwide, and soon entered the vernacular. ... gender identity is your own sense or conviction of maleness or femaleness." John Money, 'The concept of gender identity disorder in childhood and adolescence after 39 years', Journal of Sex and Marital Therapy 20 (1994): 163-77.
- , Richard G. Kopf, Edward Nersessian, Textbook of Psychoanalysis, (American Psychiatric Association, 1996), p. 645.
- John Money, 'The concept of gender identity disorder in childhood and adolescence after 39 years', Journal of Sex and Marital Therapy 20 (1994): 163-77.
- Error on call to Template:cite book: Parameter title must be specifiedHenslin, James M. (2001). pp. 65–67, 240. Taylor & Francis.
- Blackless, Melanie; Besser, M., Carr, S., Cohen-Kettenis, P.T., Connolly, P., De Sutter, P., Diamond, M., Di Ceglie, D. (Ch & Adol.), Higashi, Y., Jones, L., Kruijver. F.P.M., Martin, J., Playdon, Z-J., Ralph, D., Reed, T., Reid, R., Reiner, W.G., Swaab, D., Terry, T., Wilson, P., Wylie. K. (2003). "Atypical Gender Development – A Review". International Journal of Transgenderism 9: 29–44. http://www.gires.org.uk/genderdev.php. Retrieved 2008-09-28.