talcum (n.)

1580s, talke, from French talc (16c.), probably from Spanish talco and Medieval Latin talcus, also talcum "talc" (ealy 14c.), both from Arabic talq, from Persian talk "talc." "It was applied by the Arab and medieval writers to various transparent, translucent and shining minerals such as talc proper, mica, selenite, etc." [Flood]. Related: Talcoid; talcose; talcous.