Pounce n.
1. A fine powder, as of sandarac, or cuttlefish bone, -- formerly used to prevent ink from spreading on manuscript.
2. Charcoal dust, or some other colored powder for making patterns through perforated designs, -- used by embroiderers, lace makers, etc.
Pounce box, a box for sprinkling pounce.
Pounce paper, a transparent paper for tracing.