Source : Webster's Revised Unabridged Dictionary (1913)

Lotto \Lot"to\, n. [F. loto or It. lotto, prop., a lot; of
   German origin. See {Lot}.]
   A game of chance, played with cards, on which are inscribed
   numbers, and any contrivance (as a wheel containing numbered
   balls) for determining a set of numbers by chance. The player
   holding a card having on it the set of numbers drawn from the
   wheel takes the stakes after a certain percentage of them has
   been deducted for the dealer. A variety of lotto is called
   {keno}. [Often written {loto}.]

Source : WordNet®

lotto
     n : a game in which numbered balls are drawn at random and
         players cover the corresponding numbers on their cards
         [syn: {bingo}, {beano}, {keno}]