Talcum powder (French chalk): talc or soapstone ground and washed to a fine, slippery white powder. Used to reduce friction (a spindle bowl, boots, rubber), as a dusting and developing powder on dark surfaces, a tailor's marker, a filler in paper, paint and ceramics, and in cosmetic powders. Only talc tested free of asbestos is safe to use; do not breathe the dust.