| Gender identity | An individual's innate sense of feeling male, female, neither, or some combination of both. |
| Natal or birth-assigned/birth-designated sex | Typically assigned/designated according to external genitalia or chromosomes. |
| Gender expression | How gender is presented to the outside world (eg, feminine, masculine, androgynous); gender expression does not necessarily correlate with birth-designated sex or gender identity. |
| Gender diversity | Variation from the cultural norm in gender identity, expression, or gender role behavior (eg, in choices of toys, playmates); "gender diversity" acknowledges the spectrum of gender identities and replaces "gender nonconformity," which has negative and exclusionary connotations. |
| "Transgender" ("trans" as an abbreviation) | Umbrella term that is used to describe individuals with gender diversity; it includes individuals whose gender identity is different from their birth-designated sex and/or whose gender expression does not fall within stereotypical definitions of masculinity and femininity; "transgender" is used as an adjective ("transgender people"), not a noun ("transgenders"). |
| Gender dysphoria or incongruence | Distress or discomfort that may occur when gender identity and birth-designated sex are not completely congruent. |
| Transsexual | Older, clinical term that has fallen out of favor; historically, it was used to refer to transgender people who sought medical or surgical interventions for gender affirmation. |
| Sexual orientation | An individual's pattern of physical and emotional arousal (including fantasies, activities, and behaviors) and the gender(s) of persons to whom an individual is physically or sexually attracted (gay/lesbian, straight, bisexual); sexual orientation is an entirely different construct than gender identity, but is often confused with it; the sexual orientation of transgender people is based upon their identified gender (eg, a transgender man who is attracted to other men might identify as a gay man; a transgender woman who is attracted to other women might identify as a lesbian). |
| Sexual behaviors | Specific behaviors involving sexual activities that are useful for screening and risk assessment; many youth reject traditional labeling (homosexual, heterosexual, bisexual) but still have same-sex partners. |
| Transgender man/transman/transmasculine person | Person with a masculine gender identity who was designated a female sex at birth. |
| Transgender woman/transwoman/transfeminine person | Person with a feminine gender identity who was designated a male sex at birth. |
| Nonbinary gender identity | Person of any birth-designated sex who has a gender identity that is neither masculine nor feminine, is some combination of the two, or is fluid. Other terms that may be used for nonbinary gender identity include genderqueer, gender creative, gender independent, bigender, noncisgender, agender, two-spirit, third sex, and gender blender. |
