The distinction made by the president reflects a growing movement to emphasize that the two words mean different things. According to the World Health Organization, sex “refers to the biological and physiological characteristics that define men and women,” while gender “refers to the socially constructed roles, behaviours, activities, and attributes that a given society considers appropriate for men and women.”

As an example, the WHO gives “women earn[ing] significantly less money than men for similar work” in the United States as something that constitutes a “gender characteristic.”

While this statement seems to mark the first time the White House has distinguished between the two terms, it’s not the only instance of the administration wading into gender identity.