8.1a Gender and Sex Categorization

In the United States, people often use the terms “sex” and “gender” interchangeably. Still, sociologists recognize that they refer to two distinct yet linked concepts. At the micro level, sociologists use the term gender to refer to the behaviors, attitudes, and presentation of self (see Chapter 4) that a social group associates with biological sex (male and female). Parents, for example, give their daughters dolls to socialize them into nurturing roles. In contrast, they give sons toy weapons to socialize them into protective and tough roles. As a result, nurturing is often associated with femininity, while toughness is often associated with masculinity.

The term gender binary describes a system or structure that recognizes only two gender categories: boy/girl and man/woman. The United States culture and government has long enforced a gender binary system that has only recently begun to shift. For example, between 2022 and 2025, U.S. citizens could receive a passport with an “X” as their sex marker or a sex marker that differed from their birth sex (Duster, 2022). Several states also allow for nonbinary options for birth certificates and driver’s licenses (Reuters Staff, 2019).

However, in 2025, President Donald J. Trump signed an executive order to “restore biological truth to the federal government,” upending these inclusion efforts (The White House, 2025). As explained later in this chapter, the biological reality of sex is that there is sex variation rather than a binary. Further, many historical and contemporary cultures recognize more than two genders. Several North American Indigenous groups have long had language to describe people of nonbinary gender (Smithers, 2022). In South Asia, a third gender has been culturally recognized for centuries and, more recently, legally recognized by the governments of India, Bangladesh, and Pakistan.

Photo 8.3

Hijras Are Recognized as a Third Gender in South Asia

Performing hijra dancer [Photograph]. Instants from Getty Images Signature via Canva Pro.

In the United States, the enforcement of a sex binary starts at birth, when infants are assigned a sex category. Sex categorization is based mainly on the form of an infant’s external genitalia. While these anatomical features are biological and genetic, that does not mean sex categories are inherently natural. Culture decides which physical features count as male or female, and physical bodies do not consistently conform to binary sex categories. For example, the category intersex includes an array of conditions when anatomy, chromosomes, or other physical features do not correspond neatly to a binary sex category. In recognizing intersex conditions and accepting that sex and gender do not always match with one another, the American Medical Association (2021) recommends that governments exclude the sex category from public birth certificates.

Individuals have a gender identity. A person’s gender identity refers to the gender category with which they identify. When an individual’s birth sex category and gender category assignments match, they are called cisgender. Cisgender means their gender identity, or how they feel inside, matches the sex and gender categories they were assigned at birth. To be transgender means a person’s gender identity does not match their assigned birth sex and gender. Transgender people face many obstacles in daily life, ranging from having the incorrect sex listed on their birth certificates to facing risks to their safety. For example, transgender people have higher rates of being a victim of a violent crime compared to cisgender people (Flores et al., 2021).

A person’s sex and gender identity may change over time, or be gender-expansive. Gender nonconforming refers to how a person’s identity or behavior does not conform to the norms linked with their gender. Cisgender, transgender, and non-binary people can be gender nonconforming. For example, a cisgender woman may wear clothing and have interests more often associated with men.

Photo 8.4

Girls Using Tools Is an Example of Gender Nonconformity

Two tomboys [Photograph]. mediaphotos from Getty Images Signature via Canva Pro.