n.
Function: noun
Date: 14th century
1 : something twice the usual size, strength, speed, quantity, or value: as a : a double amount b : a base hit that enables the batter to reach second base
2 : one that is the counterpart of another : DUPLICATE : as a : a living person that closely resembles another living person b : WRAITH c (1) : UNDERSTUDY (2) : one who resembles an actor and takes his or her place especially in scenes calling for special skills (3) : an actor who plays more than one role in a production
3 a : a sharp turn (as in running) : REVERSAL b : an evasive shift
4 : something consisting of two paired members: as a : FOLD b : a combined bet placed on two different contests c : two consecutive strikes in bowling
5 plural : a game between two pairs of players
6 : an act of doubling in a card game
7 : a room (as in a hotel) for two guests ― compare SINGLE 4
– on the double : very quickly : RIGHT AWAY