pounce 2 
(pouns)
(pouns)n.
1. A fine powder formerly used to smooth and finish writing paper and soak up ink.
2. A fine powder, such as pulverized charcoal, dusted over a stencil to transfer a design to an underlying surface.
tr.v. pounced, pounc·ing, pounc·es
1. To sprinkle, smooth, or treat with pounce.
2. To transfer (a stenciled design) with pounce.
[French ponce, from Old French, from Vulgar Latin *pōmex, *pōmic-, from Latin pūmex, pumice.]
pouncer n.