Sex
Sex refers to the aspects of a person's biology which are sexually dimorphic. It is divided into three categories; genotypic/chromosomal sex, phenotypic sex, and gonadal sex. This includes chromosomes, hormone levels, genitalia, gonads, gametes, and secondary sex characteristics such as breast size, hip to waist ratio, body hair, and voice pitch. These characteristics are sometimes viewed as being a person's gender; however, sex and gender are generally considered separate concepts.
Although each person's sex characteristics are slightly different, sex is often grouped broadly into two categories: male and female, referred to as binary or dyadic sexes. Sex is typically assigned at birth based on external physiology and may not reflect how a person prefers to be characterized as later in life. People whose sex cannot be categorized clearly as male or female are referred to as intersex and many are given "corrective" surgery without their consent so that their biology more closely matches male or female.
Unlike gender expression, sex characteristics can typically only be altered through medical treatment, such as surgery or hormone replacement therapy. Transgender people often undergo such treatments as part of their transition. Cisgender people may also alter their sex characteristics through medical treatments, such as by taking hormone replacement therapy (e.g. to relieve symptoms of menopause or low T) or undergoing a mastectomy (e.g. to treat breast cancer). Sex characteristics which do not align with gender identity can result in dysphoria.
Referring to transgender people via their sex is typically seen as disrespectful, as people prefer to be viewed as their gender. In cases where gender is considered irrelevant, such as certain medical settings, it is sometimes more important to consider a person's individual biology and history than which broad categorization they fall under.
Since sex cannot be defined by a single characteristic, even if not alone, it is up to a varsex individual to decide their own sex by the traits they have, given that they defy cis-perisex standard concepts of biological sex.[1] Put simply, if one is intersex or/and transsex, their biological sex is self-determinant. Sex is traditionally defined solely by gamete dimorphism, but such ideas have become increasingly rejected,[2] as it would imply infertile individuals are sexless. In modern biology, sex is viewed as a spectrum that is socially-constructed, and self-identified if atypical[3]