Gender Identity

ByGeorge R. Brown, MD, East Tennessee State University
Reviewed/Revised Jul 2023
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Sex refers to biological characteristics (such as genitals, chromosomes, and hormones) used to categorize a person as male or female sex. Gender identity is how people see themselves, whether masculine, feminine, or some other gender identity, which may or may not correspond sex at birth.

For most people, gender identity is consistent with their anatomic (birth) sex and their gender expression (as when someone born with male anatomy [assigned male at birth] has an inner sense of masculinity and behaves in ways viewed as masculine in his society). The term cisgender, which applies to the majority of people, is used to refer to people whose gender identity corresponds to their sex assigned at birth. Some people feel that their gender identity does not match their birth sex. This is called being transgender or gender diverse.

Gender identities include traditional masculinity or femininity. However, definitions and categorizations of gender role may differ across cultures and societies. There is a growing recognition that some people do not fit into the traditional, binary, male or female gender identities. These people may refer to themselves as gender nonbinary or genderqueer.

Various terms are used to talk about sex and gender:

  • Sex refers to biological characteristics, such as genitals, chromosomes, and hormones, used to categorize a person as male or female sex. (Rarely, people are born with ambiguous genitals that include both male and female characteristics, which is called intersex.) When a person is transgender, a phrase used to refer to their birth sex is "sex assigned at birth"; a person may be a male assigned at birth (AMAB) or female assigned at birth (AFAB).

  • Gender identity is how people see themselves, whether as masculine, feminine, or some other gender identity, which may or may not correspond to the sex they were assigned at birth. Examples of gender-diverse identities include transgender, genderqueer, gender nonbinary, and other gender identities.

  • Gender expression is how people present themselves in public in terms of gender. It may include the way people dress, speak, or wear their hair.

  • Cisgender describes people whose gender identity and gender expression align with the sex assigned at birth.

  • Transgender is a general term that describes people with gender identities or gender expressions that differ from those typically associated with the sex they were assigned at birth. (Transsexual is an outdated term that is no longer used by experts in gender identity.)

  • Gender nonconforming describes people whose gender identity or gender expression differs from the gender norms associated with the sex they were assigned at birth.

  • Gender nonbinary describes people who have more than one gender identity simultaneously or at different times.

  • Genderqueer describes people whose gender identity is not strictly male or female and may include both or neither.

  • Sexual orientation: Pattern of emotional, romantic, and/or sexual attractions that people have toward others.

(See Definitions of Terminology Regarding Sex and Gender for expanded definitions of these and other terms.)

Gender identity is usually well-established by early childhood. However, at any age, some people may begin to feel that their gender identity does not match their birth sex.

Children sometimes prefer activities considered by many in their society to be more appropriate for the other sex (gender-nonconforming behavior). For example, young girls may like to play football and wrestle. Young boys may play with dolls and prefer not to take part in rough types of play. Many cultures are more tolerant of gender-nonconforming behaviors in young girls than in boys.

These types of behavior are part of normal development. It does not mean that children have a gender identity that is different from the one typically associated with their sex at birth. However, some children who express gender-nonconforming behavior do identify as transgender, and some may continue to have a gender-diverse identity as adults.

A small number of children are born with ambiguous genitals, and the management of their medical care and gender identity should involve health care professionals with specialized training and experience in this area.

Having a gender-diverse identity is a normal variant of human gender identity and expression; it is not considered a mental health disorder. Some transgender people experience significant emotional distress or difficulties with daily activities, and they should see a health care professional to be evaluated for a condition called gender dysphoria.

People with a gender identity that differs from the one typically associated with their birth sex may want to change their gender expression (gender transition). They may seek help and support from friends, family, support groups, or health care professionals to make decisions about and take steps to do one or both of the following:

  • Make a social transition (for example, by living as their identified gender)

  • Make a medical transition (for example, by taking medications or undergoing surgery to change physical characteristics to match the gender with which they identify)

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  1. American Psychological Association: Definitions of transgender terms.

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