tic-tac-toe /ˌtɪkˌtækˈto/
  一字棋
  tic-tac-toe
       n : a game in which two players alternately put crosses and
           circles in one of the compartments of a 3-by-3 board; the
           object is to get a row of three crosses or three circles
           before the opponent does [syn: ticktacktoe, ticktacktoo,
            tick-tack-toe, tit-tat-toe, noughts and crosses]