Gender refers to the social, psychological, cultural, and behavioral characteristics associated with being a man (or boy), a woman (or girl), or identifying as a third gender. While gender often matches a person’s sex assigned at birth, some individuals, such as transgender people, may identify with a gender different from the one they were assigned at birth. Many cultures follow a strict gender binary, which divides people into two groups, but some individuals do not fit into these categories and may be described as non-binary. In certain societies, there are recognized third or additional genders, such as hijras in South Asia and two-spirit people among some Native American communities. Scholars widely agree that gender plays a key role in how societies are organized, including through social roles and how people express their gender.

The word "gender" has sometimes been used interchangeably with "sex," but this usage has changed over time. In the mid-20th century, a distinction between biological sex and gender began to develop in fields like psychology, sociology, and feminism. Before this time, the term "gender" was rarely used outside of grammar. In the 1970s, feminist theory in the West helped promote the idea that biological sex and the social concept of gender are different. Today, many scientists, legal systems, and organizations, such as the World Health Organization, recognize this distinction. The experiences of intersex individuals show that both sex and gender can vary in complex ways, with people identifying as female, male, or other genders.

The study of gender is a field within the social sciences. Other areas, such as psychology, sociology, and neuroscience, also examine gender. Social sciences often view gender as a social construct, meaning it is shaped by society, while natural sciences explore whether biological differences between males and females affect how gender develops. Research in both areas helps understand how biology and society influence gender identity and behavior. Approaches that combine biology, psychology, and culture are used to study gender in a comprehensive way.

Etymology and usage

The word "gender" in modern English comes from Middle English words like "gender" and "gendre," which were borrowed from Anglo-Norman and Middle French. These words, in turn, came from the Latin word "genus." All of these words mean "kind," "type," or "sort." They originally came from a Proto-Indo-European root, *ǵénh₁-, meaning "to beget." This root is also the source of English words like "kin," "kind," and "king," as well as similar words in many other Indo-European languages. The word "genre" in French and "gene" in English also come from this root. In 1882, the Oxford Etymological Dictionary defined "gender" as "kind, breed, sex," based on the Latin word "genus." By 1900, the Oxford English Dictionary noted that the original meaning of "gender" as "kind" was no longer commonly used.

The modern idea of "gender" as a social concept is a recent development in human history. Ancient societies did not understand "gender" in the same way that it is studied today in the humanities and social sciences. For most of history, the word "gender" was linked to grammar, not to social roles. For example, in a list of 12,000 references on marriage and family from 1900 to 1964, the word "gender" did not appear at all. Analysis of over 30 million academic article titles from 1945 to 2001 showed that the word "gender" was used much less than "sex" early in this period, often referring to grammar. By the end of this period, "gender" was used more often than "sex" in social sciences, arts, and humanities. In the 1970s, feminist scholars began using "gender" to describe socially constructed differences between males and females, separate from biological differences.

As of 2024, many dictionaries list "synonym for 'sex'" as one of "gender's" meanings, along with its sociocultural meaning. The Oxford English Dictionary says "gender" began being used as a synonym for "sex" in the 20th century, initially as a more polite way to avoid the word "sex" when it was used to mean sexual activity. In the late 20th century, "gender" was often used as a synonym for "sex" in non-sexual contexts, especially outside the social sciences. However, in the natural sciences, "gender" was more often used as a synonym for "sex." This shift was influenced by feminist ideas. Scientists sometimes chose "gender" instead of "sex" to show support for feminist goals, to use a more academic term, or to avoid the idea of sexual activity. "Gender" became the preferred term when discussing issues where the cause was unclear or debated, such as whether a trait was social, biological, or both. In 1993, the U.S. Food and Drug Administration (FDA) started using "gender" instead of "sex" to avoid confusion with sexual activity. However, in 2011, the FDA changed its policy, using "sex" for biological categories and "gender" for a person's self-identity or how society responds to their appearance.

In legal cases about discrimination, a 2006 article by Meredith Render noted that as ideas about "gender" and "sexuality" changed, legal interpretations of what "discrimination because of sex" meant also changed. In 1999, Julie Greenberg wrote that although laws often use the word "sex," courts and agencies sometimes use "gender" instead when explaining these laws. In a 1994 U.S. Supreme Court case, the court stated that the Equal Protection Clause forbids discrimination based on "gender," acknowledging a long history of "sex discrimination" in the United States. The court emphasized that gender-based classifications require special attention because they reinforce stereotypes about men and women.

The word "gender" was still widely used in the grammatical sense (assigning nouns to categories like masculine, feminine, or neuter) in many languages. Aristotle wrote that this idea was introduced by the Greek philosopher Protagoras. In 1926, Henry Watson Fowler said the word's definition related to grammar. In 1945, Madison Bentley defined "gender" as "the socialized obverse of sex." Simone de Beauvoir's 1949 book, The Second Sex, is often seen as the start of the distinction between "sex" and "gender" in feminist theory, though some scholars disagree.

The term "gender role" was first used in print in 1955 by John Money, a controversial sexologist. He defined it as "all those things that a person says or does to disclose himself or herself as having the status of boy or man, girl or woman." The modern academic use of "gender" to describe social roles for men and women dates back at least to 1945. This idea was popularized by the feminist movement starting in the 1970s, which argued that social differences based on sex are not natural but are created by society. In this context, issues related to how society shapes these differences are called "gender" issues.

The common use of "gender" as a replacement for "sex" (a biological category) is widespread, though efforts continue to keep the distinction between the two. The American Heritage Dictionary (2000) used two sentences to show the difference, noting that the distinction "is useful in principle, but it is by no means widely observed, and considerable variation in usage occurs at all levels."

Biological factors and views

Some behaviors linked to gender are influenced by exposure to male sex hormones before birth and during early life. These behaviors include typical play activities for a person's gender, how they identify their own gender, and tendencies to act in aggressive ways. In most mammals, including humans, males often engage in rough-and-tumble play, which may be affected by the level of testosterone in their mothers during pregnancy. These hormone levels might also influence sexuality, with some people who are not heterosexual showing behaviors that differ from typical expectations for their assigned sex at birth.

Research has explored the biological reasons behind gender incongruence. Both transgender and cisgender identities are influenced by genetic factors. Scientists have suggested that these identities might also be shaped by hormone levels in the womb or differences in brain structure between males and females.

Studies have examined women with a condition called congenital adrenal hyperplasia (CAH), which causes their bodies to produce too much of the male sex hormone, androgen. These women typically have female physical characteristics (though many receive medical treatments to correct genital differences at birth). Even after receiving hormone treatments as children, these women are more likely to prefer activities usually associated with males than those linked to females. Dr. Sheri Berenbaum, a psychology professor who studies CAH, believes this is due to higher levels of male hormones in the womb during their development.

In research on non-human animals, the term "gender" is often used to describe biological sex. Biologist Michael J. Ryan explains that the concept of gender identity, which involves how people see themselves as male or female, applies only to humans. In a letter, Ellen Ketterson wrote that her colleagues in Gender Studies agree that "gender" is a human concept tied to culture and self-identity, while "sex" refers to biological differences. Poiani (2010) noted that it is unclear whether behaviors shared by animals across species can be linked to gender identity, as mental states like self-awareness are more developed in humans due to language. He suggested that only a few species might have members with a sense of gender identity, as it requires self-consciousness.

Jacques Balthazart stated that there is no animal model for studying how individuals identify their own sex, as it would require asking an animal about its own gender, which assumes self-awareness. He noted that this is not proven, even though some non-human animals, like primates, show advanced thinking skills. Hird (2006) wrote that it is difficult to determine if non-human animals see themselves as feminine or masculine, as this would require defining what femininity or masculinity means for each species. However, she said that non-human animals experience gender-related behaviors to the extent that their actions are divided by gender in their species.

Despite this, Poiani and Dixson argue that the concept of gender roles can be applied to non-human animals, such as rodents and primates like rhesus monkeys. In 2023, a study by Neves et al. found small but meaningful details in how communication, such as grammatical gender categories in language, contributes to stereotypes and emotions associated with four non-human animals: giant pandas, giraffes, polar bears, and cheetahs.

Feminist theory

Biologist and feminist scholar Anne Fausto-Sterling believes that the debate between biology and society as the main factors in shaping people is too simple. Instead, she argues that understanding how biology and the social environment work together is important.

Philosopher and feminist Simone de Beauvoir used existentialism to explain how women's lives are shaped. She said, "One is not born a woman, one becomes one." This means that becoming a woman involves both biological changes, like puberty, and learning social behaviors through experience.

During the 1970s, feminist theory developed new terms to describe gender issues. In 1974, a book called Masculine/Feminine or Human used terms like "innate gender" and "learned sex roles." By 1978, the book changed to use "sex" and "gender" differently. By 1980, most feminist writings agreed to use "gender" only for traits influenced by culture and society.

Andrea Dworkin, a feminist, said she wanted to end male dominance and the concept of gender. She supported radical feminism, which focuses on deep changes in society.

Political scientist Mary Hawkesworth studied how the concept of gender changed in feminist theory since the 1970s. She noted that scholars like Sandra Harding and Joan Scott started using gender as a way to analyze how people think about and organize social activities. Feminist scholars in political science began using gender as an analytical tool, which helped highlight social and political relationships that were often ignored. However, Hawkesworth pointed out that feminist political science is not the main approach in the field yet.

Gender studies

Gender studies is a field of study that combines ideas from many different subjects. It focuses on understanding how gender, gender identity, and how people are represented based on their gender are important for analyzing the world. This field includes the study of women, men, and LGBTQ (lesbian, gay, bisexual, transgender, and queer) issues. Sometimes, gender studies is taught along with the study of sexuality. These areas of study look at gender and sexuality in subjects like literature, history, politics, sociology, anthropology, film, human development, law, and medicine. They also examine how race, ethnicity, where people live, their nationality, and disabilities affect experiences.

In gender studies, the word "gender" refers to how societies and cultures create ideas about what it means to be masculine or feminine. This focus does not include biological differences, such as differences between male and female bodies. This idea came from different areas, including sociology in the 1950s, the work of psychoanalyst Jacques Lacan, and the research of French thinkers like Julia Kristeva and Luce Irigaray, as well as American feminists like Judith Butler. People who followed Butler believed that gender roles are something people do, often called "performative" actions.

Charles E. Hurst explains that some people think biological sex automatically determines how someone behaves, their social role, and their sexual orientation (who they are attracted to). However, sociologists who study gender believe that people learn how to act based on cultural ideas about gender. For example, Michael Schwalbe says that humans are taught how to behave in ways that fit traditional ideas of being masculine or feminine. Schwalbe notes that people act on shared cultural ideas through choices like clothing, hairstyles, relationships, and jobs. These differences are important because society wants to categorize people quickly, placing them into groups to understand how to treat them.

Hurst explains that in societies where gender is clearly defined, breaking these rules can lead to serious consequences. These consequences often involve discrimination based on sexual orientation. Gays and lesbians face discrimination in the legal system because of societal biases. Hurst says that courts often mix up the ideas of sex, gender, and sexual orientation, leading to unfair treatment of people who do not fit traditional gender expectations, regardless of their sexual orientation. This bias shows up in the legal system when someone is treated differently because they do not act in a way society expects for their sex.

Karen Beckwith, an American political scientist, discusses how gender is used in political science. She says that a shared understanding of gender must be clearly defined to use it effectively in research. Beckwith explains that political scientists can use gender in two ways: as a category and as a process. Using gender as a category helps researchers study how behaviors, actions, and attitudes linked to being masculine or feminine lead to specific political outcomes. It also shows how gender differences, which may not match biological sex, can affect political actors. Using gender as a process includes looking at how structures and policies impact men and women differently, and how masculine and feminine political figures work to create outcomes that favor their gender.

Jacquetta Newman explains that while biological sex is determined by science, how people express their gender is shaped by society. She says that cultural expectations about men and women are often connected to biology, but this can lead to focusing too much on sex as the cause of oppression while ignoring other issues like race, ability, and poverty. Modern gender studies classes aim to explore how these factors interact to affect people's lives. Newman also notes that non-Western cultures may have different views on gender and roles. She argues that the term "equality," often seen as a goal of feminism, is unclear because it can mean treating people the same, differently, or fairly based on gender. Newman believes this lack of a clear definition is important in areas like public policy.

Gender identity refers to how a person personally identifies with a specific gender and the roles society expects of that gender. The term "woman" has historically been used to describe the female body, but some feminists now find this usage controversial.

Some studies explore how gender is represented in society, but feminists challenge the idea that gender roles and biological sex are fixed. Often, a person's biological sex is tied to social roles and expectations. Judith Butler says that being a woman involves challenges because society sees women as both a social group and a personal identity shaped by culture. Social identity refers to how people connect with groups or categories that shape shared cultural values. According to social identity theory, a key part of how people see themselves comes from their membership in social groups. These group connections influence how people view themselves and behave in society.

Putting people into male or female roles can be difficult for some individuals who feel they do not fit into strict categories of man or woman. Globally, societies use biological differences between men and women to create expectations about what behaviors are "appropriate" for each gender. These expectations affect access to rights, resources, power, and health behaviors. While these expectations vary across cultures, they often favor men, leading to power imbalances and gender inequalities. Many cultures have different beliefs about gender, but there is no universal standard for what masculine or feminine roles should be. The roles of men and women in relation to each other depend on the cultural norms of a society, which shape the gender systems that influence social patterns.

Psychology and sociology

Many complex human behaviors are shaped by both natural factors, such as genes and body chemistry, and by environmental factors, like diet, social pressures, and culture. A major area of study in behavioral psychology gathers information to find connections between behaviors and possible causes, including genetics, access to food, culture, hormones, and social environments.

A key area of research in sociology focuses on how human behavior affects other people or groups. Starting in the late 20th century, the feminist movement has contributed many studies on gender and related theories, not only in sociology but also in other fields.

Social theorists have tried to understand how gender is connected to biological sex and sexuality. As a result, society often treats gender and biological sex as similar, even though they are different. Some ideas from the second wave of feminism, which argue that gender is created by society and is dominant in all cultures, are still used in certain areas of literary theory, such as in research by Kira Hall and Mary Bucholtz as recently as 2008.

As children grow, society provides examples of behaviors that are considered appropriate for boys or girls. This process teaches children to fit into culturally defined gender roles. There is strong motivation for children to follow these social expectations, as gender influences opportunities in education, work, family life, and the ability to shape culture and knowledge. Adults who do not follow these expected roles are often seen as not properly socialized or as deviant.

Some believe that society divides gender into two groups through organizations that create and repeat cultural images of gender. Joan Acker identified five social processes that contribute to gendering:

• Creating divisions based on gender, such as differences in labor, power, family roles, and where people are allowed to be in physical spaces.
• Creating symbols and images, like language, media, and clothing, that explain or reinforce these divisions.
• Interactions between people of different genders, including patterns of dominance or submission, such as how conversations can reflect gender inequality.
• How these processes shape individual identity, creating a sense of being male or female.
• How gender influences the creation and understanding of social structures.

When studying gender through the ideas of Michel Foucault, gender is seen as a way to divide power in society. Gender differences are not natural but are created by society to enforce differences between what is considered male and female, allowing for the dominance of masculinity over femininity by assigning specific traits to each gender. The belief that men and women are more different from each other than from other groups is not based on nature but on social ideas that ignore natural similarities.

Societal rules and cultural traditions assign masculine or feminine traits to biological sex. These rules, which are both created by society and help define how society functions, determine how traits are given to each sex. These traits form the basis for dominant gender differences. This means that gender can be understood as learning and accepting social norms. People are taught by society’s expectations about what is considered acceptable for each gender, as seen in institutions like families, governments, and the media. These expectations become part of a person’s identity, making gender a social category that is applied to a biological sex.

The idea that people are gendered rather than sexed aligns with Judith Butler’s theory of gender performativity. Butler argues that gender is not about who someone is but about what someone does. Repeating these actions reinforces gender roles in society. Today, sociologists often use terms like "masculinities" and "femininities" in the plural form, showing that gender roles vary within and across cultures.

The difference between how sociology and the general public define gender lies in their focus. Sociology studies how gender relates to social roles, such as comparing a male CEO’s position to female workers, without considering sexual orientation. In contrast, the popular definition focuses on personal identity, such as differences between people who identify as gay or straight, without considering economic or power differences between genders. This creates a tension between traditional feminist sociology and modern studies on sexuality.

Gender as biopsychosocial

According to Alex Iantaffi, Meg-John Barker, and others, gender is influenced by biological, psychological, and social factors. These factors work together and affect each other to shape a person’s gender.

Biological factors, such as sex chromosomes, hormones, and body structures, are important in how gender develops. Hormones like testosterone and estrogen help shape how a person experiences and expresses their gender. Body structures, such as genitalia and reproductive organs, also play a role in how a person understands and shows their gender.

Psychological factors, such as how people think, their personality, and how they see themselves, also affect gender. A person’s sense of being male, female, or another gender often begins to develop between the ages of two and three. How someone shows their gender, called gender expression, is influenced by culture, personal choices, and differences in personality.

Social factors, such as customs, how people are taught, and rules in places like schools and workplaces, also shape how people understand and express their gender.

In some English writing, gender is divided into three parts: biological sex, psychological gender, and social gender roles. This idea first appeared in a feminist paper about transsexualism in 1978.

Gender and society

Grammatical gender is a feature in some languages where every noun is assigned a gender, even if it has no connection to the noun’s meaning. For example, the word for "girl" is "muchacha" (feminine) in Spanish, "Mädchen" (neuter) or "Maid" (feminine) in German, and "cailín" (masculine) in Irish. The term "grammatical gender" is also used for more complex systems that include categories like masculine, feminine, and other features such as whether something is living or made by humans. An example is the Dyirbal language, which has a category for fruit and vegetables. Other languages, like Ojibwe and Basque, use categories such as animate (living things) and inanimate (non-living things). Some languages, such as those in the Dravidian family, separate people (including gods) from all other things.

A study of 258 languages found that fewer than half have grammatical gender. Of the remaining languages, more than half have more than two genders. Grammatical gender can be based on biological sex, whether something is living, or other features. Some languages, like those in the Niger-Congo family, have up to 20 genders, including categories for plants and shapes.

Many languages use different words for men and women. Some people worry that language might favor men, so they suggest using more neutral words in English and other languages. Some languages, like Persian and Hungarian, do not use gendered words. In Persian, the same word is used for men and women, and verbs, adjectives, and nouns are not gendered. Other languages, such as Navajo, use more than two genders to describe people.

A person’s gender can affect legal rights. In some countries, same-sex marriage is legal. Transgender people face different legal situations worldwide. Some countries protect transgender rights, while others punish gender identity or expression. Many countries now allow people to change their legal gender on documents like birth certificates.

Intersex people, who do not fit typical ideas of male or female bodies, may struggle to get identification documents with a gender marker. Some intersex people seek non-binary recognition, which is now legal in countries like Canada, Germany, and Australia. In the U.S., Oregon was the first state to legally recognize non-binary gender in 2017.

Historically, science was seen as a male field, and women faced barriers to participation. Even after women were allowed in universities, they were often limited to fields like nursing or child psychology. They were given low-paying jobs and denied leadership roles. These stereotypes have been challenged, but women remain underrepresented in fields like physics. Global efforts, such as the United Nations’ goals, aim to address this.

Religious beliefs often include ideas about gender. In Taoism, yin (feminine) and yang (masculine) are balanced forces. In Judaism, God is traditionally described as male, but the Kabbalah tradition includes a feminine aspect called Shekhinah. Judaism teaches that God has no gender, but traditional roles for men and women still exist, though some modern groups support equality. Judaism recognizes at least six genders.

In Christianity, God is often described as male, and the Church is sometimes seen as female. However, Christian teachings emphasize that God transcends gender and is fully represented in both male and female traits. In Hinduism, the god Shiva is shown as Ardhanarishvara, a form with both male and female halves. This symbolizes the balance between creative and destructive forces in the universe. It reflects the idea that all humans have both male and female energies within them.