The sex assigned to an individual when born; that is, typically, male or female as it may appear on one’s birth certificate.

A transgender individual is somebody who identifies their gender differently to their sex assigned at birth. By comparison, someone whose sex assigned at birth is the same as their gender (that is, their sex and gender are aligned) is considered cisgender.

It should be noted, however, that medical professionals are increasingly recognising those born with intersex variations, and may mark documents such as birth certificates as ‘X’ or ‘indeterminate’ – however, this should not be taken to mean that all people with intersex variations are of an indeterminate sex: it is common for intersex people to identify with their sex assigned at birth (male or female). A further issue presented in regards to people with intersex variations and sex assigned at birth is the issue of so-called ‘corrective surgery‘, in which medical practitioners conduct unnecessary, often cosmetic, surgery on intersex infants to ‘normalise’ their bodies to look more typically male or female.

Also known as designated sex at birth (DSAB), sex coercively assigned at birth (SCAB).

Related: assigned male at birth (AMAB), assigned female at birth (AFAB).