Definition of: double

(dub′əl) adjective
1. Having two of a sort together; being in pairs; coupled.
2. Twice as large, much, strong, heavy, valuable, or many.
3. Two-fold; hence, ambiguous, deceitful, or two-faced.
4. Doubled; folded.
5. Bot. Having the petals increased in number: said of flowers.
6. In musical instruments, making tones an octave lower.
—noun
1. Something that is twice as much.
2. A fold or plait.
3. A person or thing that closely resembles another; hence, an apparition or wraith.
4. A backward turn, as of a hunted fox; a trick or stratagem.
5. A player or singer who understudies the part of a principal artist, so as to be able to supply his or her place in case of illness, etc.; an understudy.
6. plural A tennis game between two pairs of players; also, two successive faults in tennis.
7. Eccl. A feast at which the antiphon is said both before and after the psalms.
8. In baseball, a two-base hit.
9. A domino piece bearing the same number of pips on each half.
10. In card playing, the act of doubling. See DOUBLE (v. def. 13).
11. A double·star.
—on (or at) the double In double-quick time: a military command.
—v. doub·led, doub·ling v.t.
1. To make twice as great in number, size, value, force, etc.; increase by adding an equal amount.
2. To fold or bend one part of upon another; make of two thicknesses: usually with over, up, back, etc.
3. To do over again; repeat.
4. To be twice the quantity or number of.
5. To act or be the double of.
6. In baseball, to advance (a base runner) by hitting a double: He doubled him home.
7. Naut. To sail around: to double a cape.
8. Music To add the upper or lower octave to.
—v.i.
9. To become double; increase by an equal amount.
10. To turn and go back on a course: often with back.
11. To act or perform in two capacities.
12. In baseball, to hit a double.
13. In bridge, to declare each trick in the suit last bid by an opponent to be of twice the normal value in points: done in the expectation of defeating the hand and thereby exacting an increased penalty.
—to double in brass U.S. Slang To take more than one part in anything, as in addition to one's specialty: originally said of musicians.
—to double up
1. To bend over or cause to bend over, as from pain or laughter.
2. To fold or clench, as a fist.
3. To share one's quarters, bed, etc., with another.
4. In baseball, to complete a double play upon.
—adverb
1. In twofold degree; twice.
2. In twice the quantity.
3. Deceitfully. Also doub′ly adverb [<OF duble <L duplus double]
Double, meaning two, twofold, or twice, may appear as a combining form in hyphemes, as in: