Sex / Sex assigned at birth / Biological sex
(Noun) A person's sex (male, female, or intersex) is often determined based on the appearance of the genitalia, either in ultrasound or at birth. In reality, biological sex is more complicated, referring to a combination of anatomical, physiological, genetic, and physical attributes. These include genitalia, gonads, hormone levels, hormone receptors, chromosomes, genes, and secondary sex characteristics. The phrase "sex assigned at birth" is used by some to emphasize that genitalia alone are not always a sufficient indication of a person's sex, as well as the fact that a person's gender identity is not always aligned with the sex characteristics observed at birth.