Source : Webster's Revised Unabridged Dictionary (1913)

Sandpaper \Sand"pa`per\, n.
   Paper covered on one side with sand glued fast, -- used for
   smoothing and polishing.

Sandpaper \Sand"pa`per\, v. t.
   To smooth or polish with sandpaper; as, to sandpaper a door.

Source : WordNet®

sandpaper
     n : stiff paper coated with powdered emery or sand [syn: {emery
         paper}]
     v : rub with sandpaper; "sandpaper the wooden surface" [syn: {sand}]