Gender

Gender is a term that encompasses various human traits that, in a given society, are traditionally grouped together. These traits can include learned behaviors and roles, biological traits (as understood by society), appearance, and more. In Western societies, this notion traditionally corresponds to the binary sexes, man and woman, though this is not always the case. Many non-Western cultures have traditional genders besides male and female, and there is a growing number of people, including in Western society, who identify as nonbinary or genderqueer.

Gender identity refers specifically to the internal sense of one's gender. People who identify with their assigned gender at birth (AGAB) are referred to as cisgender; those who do not are referred to as transgender. People who identify as the other binary gender than what they were assigned at birth are sometimes called binary transgender; those who identify as something else are called nonbinary or genderqueer.

While the concepts of gender and sex are related, they are not the same. However, sex, understood as the system to organize certain biological traits (rather than the traits themselves) is also a social construct and a spectrum. While the traits themselves (such as chromosomes or hormones) are biological facts, how they are classified into distinct groups is a social construct. People who don't fit either category of sex may be called intersex, but the word refers to sex only, not to gender.

History of the term
Etymologically speaking, "gender" derives from Old French gendre (in turn deriving from the Latin genus) and used to mean "class or kind of persons or things sharing certain traits". In the 15th century it began to be used as a synonym for sex until the 20th century, when it began to adopt its current meaning. Before then, although gender variance existed around the world, the abstract concept of gender itself didn't exist and was mostly associated with the grammar of certain languages.

In 1945, psychologist Madison Bentley defined gender in Sanity and Hazard in Childhood as the "socialized obverse of sex", and Simone de Beauvoir's 1949 book The Second Sex is often seen as the beginning of the distinction between the terms gender and sex. In current times, gender and sex are frequently used interchangeably, although preserving the distinction is useful, especially for educational purposes.

Relationship between sex and gender
Gender is generally assigned at birth based on the infant's genitalia. Infants with penises are assigned male and infants with vulvae are assigned female. Intersex infants with ambiguous genitalia are often subjected to surgery meant to give them the appearance of a dyadic (non-intersex) person. Then they are assigned a gender accordingly.

The majority of people identify with their AGAB, but some do not. In Western society, this makes one transgender. In other cultures, specific gender identities besides male and female are available based on the person's AGAB, their relations to people of other genders, and other factors. Some intersex people identify as intergender, a nonbinary identity that is tied to one's intersex status.

Transgender people often experience dysphoria, a dissatisfaction with or disconnect from things associated with their AGAB. This includes (but is not limited to) desires to have different sex characteristics. It is unclear how much of these desires are due to the conflation of sex and gender in society, and how much is inborn. The treatment for physical dysphoria is physical transition. Transition for trans women often involves hormone therapy with androgen blockers, estrogen, and/or progesterone; voice training; facial reconstruction surgery; vaginoplasty; and/or hair removal techniques. Transition for trans men often involves hormone therapy with testosterone; top surgery (breast removal); and/or phalloplasty. Transgender children sometimes go on puberty blockers until they decide whether to undergo hormone therapy, to avoid going through undesirable physical changes during puberty. Not all trans people choose to undergo all or any of these treatments, and nonbinary people may also undergo any number of these treatments. Some trans people choose to physically transition despite having no physical dysphoria in order to be socially recognized as the gender they are. This includes acknowledgement from friends, family, coworkers, and strangers, as well as legal documentation.

Gender identity
Gender identity is the internal sense of one's own gender, regardless of physical characteristics, appearance, behaviour or sexual orientation. People who identify with the gender they were assigned at birth are cisgender, while people whose gender identity differ from their assigned gender are transgender or nonbinary.

Gender expression
Gender expression refers outwardly visible traits that are related to one's gender identity. This includes pronouns, clothes, hairstyle, movements, inflection, speech patterns, and more. People's gender expression generally functions to communicate that person's gender to others via similarities to other people of the same gender, but there are exceptions. People whose gender expression differs from what is expected given their gender are called gender nonconforming. Sometimes transgender people have gender expressions similar to people of their AGAB because it is how they grew up presenting, and sometimes transgender people are closeted, and have a gender expression that specifically does not convey their gender to others. Many people simply enjoy playing with gender norms.

Gender roles
Gender roles refer to the way society expects people with a certain gender to behave. For example, in the traditional Western binary system, men are expected to be strong and avoid showing their feelings in public while women are expected to be soft and kind. Gender roles don't define one's gender identity, which means that, for instance, somebody can identify as a woman but behave according to the masculine gender roles and vice versa.