to double; make twice as great: to redouble one's efforts.
to echo or reecho.
to double the double of (an opponent).
to go back over: to redouble one's footsteps.
to repeat.
—v.i.
to be doubled; become twice as great.
to be echoed; resound.
to double the double of an opponent.
—n.
the act of doubling one's opponent's double.
an attack in a line other than that of the previous attack, made after the failure of the opponent to follow his or her parry of the previous attack with a riposte.