Foundational Concepts and Affirming Terminology Related to Sexual Orientation, Gender Identity, and Sex Development

Updated: May 1, 2020

Sexual Orientation (SO) is how a person defines their physical, emotional, and romantic attachments to other people. The three primary components of sexual orientation are attraction, behavior and identity, all of which may change over time for some people. Some of the more common sexual orientation identities are lesbian, gay, bisexual, queer and straight, though there are many more. 

Gender Identity (GI) is a person’s inner sense of being a woman, man, another gender, or having no gender at all. GI does not necessarily align in a traditional sense with the sex a person is assigned at birth (typically female or male). GI may also change over time for some people. 

Sex Development (SD) is the process by which biological sex characteristics emerge. One example of differences of sex development are intersex conditions, in which a person has reproductive or sexual anatomy that differs from traditional definitions of female or male biology. 

The term Lesbian, Gay, Bisexual, Transgender, Queer, and Intersex + (LGBTQI+) refers to some of the minority identities and communities that exist related to SO, GI and SD. The + refers to the existence of many additional identities. Some people identify with multiple terms within the same category (e.g., for SO, bisexual and queer). 

All people have a sexual orientation, gender identity, and sex development. This guide is to help you talk to your patients about theirs. 


A graph of 4 circles of increasing size all within one circle. Smallest circle is labeled "sex assigned at birth," the 2nd is "gender identity," the 3rd is "gender expression," the 4th and largest circle is "gender perception."




Sex assigned at birth1, inner sense of gender2, how gender is outwardly communicated3, and how gender is perceived by others4 are all separate but interrelated elements that inform individual experiences of gender. 





Name and Pronouns: Using a person’s correct name (potentially different than the name on official documents) and pronouns is vital. You cannot assume a person’s name or pronouns without asking directly. When someone shares their name and pronouns with you, it is important to learn and consistently use them. 

Commonly used pronouns include: 


Ex: “My friend Kerry likes riding their bike after work. Sometimes I go with them!” 

There are many ways people experience their sexual orientation, gender identity, and sex development— as well as different ways these identities and others, such as race/ethnicity, may intersect in one person’s experience. Everyone has a different journey, so it’s important to not make assumptions and to allow space for human complexity and diversity. While this guide shares the most common terminology, there are many other terms a person could use to describe their identity—and language is constantly evolving! What matters is learning who people are and respecting the language they use for themselves. 

Gender Term



A person whose gender identity and sex assigned at birth align in a traditional sense (eg, a man assigned a male sex at birth). Sometimes the shortened “cis” is used.


An umbrella term for people whose gender identity and sex assigned at birth do not align based on traditional expectations (eg, a man assigned a female sex at birth). Sometimes the shortened “trans” is used.

Transgender Man or Boy

A man or boy assigned a female sex at birth.

Transgender Woman or Girl

A woman or girl assigned a male sex at birth.

Nonbinary or Gender Diverse

Umbrella terms used to describe people whose gender falls outside of the traditional gender binary structure of woman or man, including individuals who identify as neither a woman nor man, who identify as both a woman and a man, or whose gender identity fluctuates or changes. Individuals in this group may or may not identify with the term “transgender.” (Other identities under this umbrella may include: Genderfluid, Genderqueer, and more.)

Gender Expression and Presentation

How someone communicates their gender through clothing, hairstyle and grooming, body language, behavior, and other aspects of outwardly displaying gender.

Intersex (sometimes called “Differences in Sex Development,” or DSD) describes diversity in sex characteristics whereby reproductive organs, genitals, or other sexual anatomy differ from traditional expectations for female or male. Sometimes intersex traits are noticed at birth and sometimes not until puberty or later. This is not the same as transgender, as sex development is different from gender identity. Intersex can be used as an identity term for someone with one of these traits. Intersex people may identify with a range of sexual orientations and gender identities. 

Sexual Orientation Definition

Describes (trans or cis) women who are primarily attracted to (trans or cis) women. Often referred to as “homosexual,” though this term is no longer used by many in the community.


Describes (trans or cis) men who are primarily attracted to (trans or cis) men. Also used and embraced by people with other gender identities to describe same-gender attractions and relationships. Often referred to as “homosexual,” though this term is no longer used.


Describes people who are attracted to people of their own gender as well as other genders, or to multiple genders that may be different from their own. (Sometimes shortened to “bi” or “bi+”.)


Describes people who experience little or no sexual attraction to others. Asexual people may still experience emotional or romantic attractions and some may still engage in sexual activity. (Sometimes shortened to “ace.”)


Describes people who are attracted to people of all gender identities and expressions, or whose attractions are not related to other people’s gender. Although some people may identify as both pansexual and bisexual, someone may identify more with one of these sexual orientations than the other.


Describes people who think of their sexual orientation or gender identity as outside of societal norms (ie, not straight or cisgender). Some people view the term queer as more fluid and inclusive than traditional identities. Although queer was historically used as a slur, it has been reclaimed by many in the LGBTQIA+ as a term of empowerment.

Straight Describes a (trans or cis) man or (trans or cis) woman who is primarily attracted to people of the other binary gender than themselves. Often referred to as heterosexual.


Updated May 1, 2020 from Carl J. Streed, Jr. (2017) by Harvard Medical School, Program in Medical Education SGM Health Equity Group: John L. Dalrymple, MD; Alex Keuroghlian, MD, MPH; Jennifer Potter, MD; Carly Guss, MD, MPH; Sabra L. Katz-Wise, PhD; Rusty Phillips, MD; Jessica Halem, MBA; Emeline Jarvie. For questions about this resource, please email

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