Source : Webster's Revised Unabridged Dictionary (1913)

Graffito \Graf*fi"to\, n. [It., fr. graffio a scratching.] (Art)
   Production of decorative designs by scratching them through a
   surface of layer plaster, glazing, etc., revealing a
   different-colored ground; also, pottery or ware so decorated;
   -- chiefly used attributively.

Source : WordNet®

graffito
     n : a rude decoration inscribed on rocks or walls [syn: {graffiti}]
     [also: {graffiti} (pl)]