paper or cardboard having different colors, finishes, or stocks on opposite sides.
4.
Printing.
a.
a method of reproducing an illustration using two halftone plates, one black and the other in a color.
b.
a printing press equipped to print both sides of a sheet in one pass.
5.
Genetics. a double-stranded region of DNA.
–adjective
6.
having two parts; double; twofold.
7.
(of a machine) having two identical working units, operating together or independently, in a single framework or assembly.
8.
pertaining to or noting a telecommunications system, as most telephone systems, permitting the simultaneous transmission of two messages in opposite directions over one channel.
–verb (used with object)
9.
to make duplex; make or change into a duplex: Many owners are duplexing their old houses for extra income.
Relating to or being a single assembly of machinery having two identical units that are capable of operating simultaneously or independently.
Electronics Of or relating to a communications mode, as in a telephone system, that provides simultaneous transmission and reception in both directions.
n.
A house divided into two living units or residences, usually having separate entrances.
1817 (adj.) "composed of two parts," from L. duplex, from duo "two" + -plex, from Gk. plax (gen. plakos) "flat surface." The noun sense of "house for two families; two-story apartment" is Amer.Eng., 1922.
Main Entry: du·plex Pronunciation: 'd(y)ü-"pleks Function: noun : a molecule having two complementary polynucleotide strands of DNA or of DNA
and RNA —duplexadjective
duplexcommunications Used to describe a communications channel that can carry signals in both directions, in contrast to a simplex channel which only ever carries a signal in one direction. If signals can only flow in one direction at a time the communications is "half-duplex", like a single-lane road with traffic lights at each end. Walkie-talkies with a "press-to-talk" button provide half-duplex communications. If signals can flow in both directions simultaneously the communications is "full-duplex", like a normal two-lane road. Telephones provide full-duplex communications. The term "duplex" was first used in wireless, telegraph, and telephone communications. Nearly all communications circuits used by computers are two-way, so the term is seldom used. (http://cit.ac.nz/smac/dc100www/dc_014.htm). (2001-07-21)
Dou"ble\, a. [OE. doble, duble, double, OF. doble, duble, double, F. double, fr. L. duplus, fr. the root of duo two, and perh. that of plenus full; akin to Gr. ? double. See Two, and Full, and cf. Diploma, Duple.]1. Twofold; multiplied by two; increased by its equivalent; made twice as large or as much, etc. Let a double portion of thy spirit be upon me. -- 2 Kings ii. 9. Darkness and tempest make a double night. --Dryden. 2. Being in pairs; presenting two of a kind, or two in a set together; coupled. [Let] The swan, on still St. Mary's lake, Float double, swan and shadow. --Wordsworth. 3. Divided into two; acting two parts, one openly and the other secretly; equivocal; deceitful; insincere. With a double heart do they speak. -- Ps. xii. 2. 4. (Bot.) Having the petals in a flower considerably increased beyond the natural number, usually as the result of cultivation and the expense of the stamens, or stamens and pistils. The white water lily and some other plants have their blossoms naturally double. Note: Double is often used as the first part of a compound word, generally denoting two ways, or twice the number, quantity, force, etc., twofold, or having two. Double base, or Double bass (Mus.), the largest and lowest-toned instrument in the violin form; the contrabasso or violone. Double convex. See under Convex. Double counterpoint (Mus.), that species of counterpoint or composition, in which two of the parts may be inverted, by setting one of them an octave higher or lower. Double court (Lawn Tennis), a court laid out for four players, two on each side. Double dagger (Print.), a reference mark ([dag]) next to the dagger ([dagger]) in order; a diesis. Double drum (Mus.), a large drum that is beaten at both ends. Double eagle, a gold coin of the United States having the value of 20 dollars. Double entry. See under Bookkeeping. Double floor (Arch.), a floor in which binding joists support flooring joists above and ceiling joists below. See Illust. of Double-framed floor. Double flower. See Double, a., 4. Double-framed floor (Arch.), a double floor having girders into which the binding joists are framed. Double fugue (Mus.), a fugue on two subjects. Double letter. (a) (Print.) Two letters on one shank; a ligature. (b) A mail requiring double postage. Double note (Mus.), a note of double the length of the semibreve; a breve. See Breve. Double octave (Mus.), an interval composed of two octaves, or fifteen notes, in diatonic progression; a fifteenth. Double pica. See under Pica. Double play (Baseball), a play by which two players are put out at the same time. Double plea (Law), a plea alleging several matters in answer to the declaration, where either of such matters alone would be a sufficient bar to the action. --Stephen. Double point (Geom.), a point of a curve at which two branches cross each other. Conjugate or isolated points of a curve are called double points, since they possess most of the properties of double points (see Conjugate). They are also called acnodes, and those points where the branches of the curve really cross are called crunodes. The extremity of a cusp is also a double point. Double quarrel. (Eccl. Law) See Duplex querela, under Duplex. Double refraction. (Opt.) See Refraction. Double salt. (Chem.) (a) A mixed salt of any polybasic acid which has been saturated by different bases or basic radicals, as the double carbonate of sodium and potassium, NaKCO3.6H2O. (b) A molecular combination of two distinct salts, as common alum, which consists of the sulphate of aluminium, and the sulphate of potassium or ammonium. Double shuffle, a low, noisy dance. Double standard (Polit. Econ.), a double standard of monetary values; i. e., a gold standard and a silver standard, both of which are made legal tender. Double star (Astron.), two stars so near to each other as to be seen separate only by means of a telescope. Such stars may be only optically near to each other, or may be physically connected so that they revolve round their common center of gravity, and in the latter case are called also binary stars. Double time (Mil.). Same as Double-quick. Double window, a window having two sets of glazed sashes with an air space between them.
Du"plex\, a. [L., fr. duo two + plicare to fold. See Two, and Complex.] Double; twofold. Duplex escapement, a peculiar kind of watch escapement, in which the scape-wheel has two sets of teeth. See Escapement. Duplex lathe, one for turning off, screwing, and surfacing, by means of two cutting tools, on opposite sides of the piece operated upon. Duplex pumping engine, a steam pump in which two steam cylinders are placed side by side, one operating the valves of the other. Duplex querela [L., double complaint] (Eccl. Law), a complaint in the nature of an appeal from the ordinary to his immediate superior, as from a bishop to an archbishop. --Mozley & W. Duplex telegraphy, a system of telegraphy for sending two messages over the same wire simultaneously. Duplex watch, one with a duplex escapement.
Du"pli*cate\, a. [L. duplicatus, p. p. of duplicare to double, fr. duplex double, twofold. See Duplex.] Double; twofold. Duplicate proportion or ratio (Math.), the proportion or ratio of squares. Thus, in geometrical proportion, the first term to the third is said to be in a duplicate ratio of the first to the second, or as its square is to the square of the second. Thus, in 2, 4, 8, 16, the ratio of 2 to 8 is a duplicate of that of 2 to 4, or as the square of 2 is to the square of 4.
Du*plic"i*ty\, n.; pl. Duplicities. [F. duplicit['e], L. duplicitas, fr. duplex double. See Duplex.]1. Doubleness; a twofold state. [Archaic] Do not affect duplicities nor triplicities, nor any certain number of parts in your division of things. --I. Watts. 2. Doubleness of heart or speech; insincerity; a sustained form of deception which consists in entertaining or pretending to entertain one of feelings, and acting as if influenced by another; bad faith. Far from the duplicity wickedly charged on him, he acted his part with alacrity and resolution. --Burke. 3. (Law) (a) The use of two or more distinct allegations or answers, where one is sufficient. --Blackstone. (b) In indictments, the union of two incompatible offenses. --Wharton. Syn: Double dealing; dissimulation; deceit; guile; deception; falsehood.
Du"plex\, v. t. [See Duplex, a.] (Teleg.) To arrange, as a telegraph line, so that two messages may be transmitted simultaneously; to equip with a duplex telegraphic outfit.
Du"plex\, v. t. [See Duplex, a.] (Teleg.) To arrange, as a telegraph line, so that two messages may be transmitted simultaneously; to equip with a duplex telegraphic outfit.
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