Definitions of powder:

noun: any of various cosmetic or medical preparations dispensed in the form of a powder
noun: a solid substance in the form of tiny loose particles; a solid that has been pulverized
noun: a mixture of potassium nitrate, charcoal, and sulfur in a 75:15:10 ratio which is used in gunnery, time fuses, and fireworks
verb: apply powder to
Example: "She powdered her nose"
verb: make into a powder by breaking up or cause to become dust