Initialism: fluorescence-activated cell sorting; a flow cytometry method separating cells by fluorescent markers.

Initialism: Facial Action Coding System; a framework to label facial muscle movements.

Initialism: family and consumer sciences; an academic field on home, nutrition, and family life.

Plural of FAC; more than one instance of the initialism FAC.

Plural of fac; decorative initial letters once used to begin sections.