When was it first coined?<p>As a verb:<p><pre><code> retard, v.
[ad. F. retarder (13th c., = Sp. and Pg. retardar, It. ritardare), or L. retardāre, f. re- re- + tardus slow.]
1.1 trans. To keep back, to delay, hinder, impede (a person or thing in respect of progress, movement, action, or accomplishment).
c 1489 Caxton Blanchardyn xxiii. 75 Here is one doubte that retardeth myne ymagynacyon.
1636 Denham Destr. Troy 423 The one retarded was By feeble age, the other by a wound.
1660 F. Brooke tr. Le Blanc's Trav. 260 The sight of this fishing retarded us above an houre.
2.2 To delay the progress or accomplishment, to impede the course, of (an action, movement, etc.).
1572 Reg. Privy Council Scot. II. 158 That sa haly a work be not retardit.
1610 B. Jonson Alch. iv. v, This'll retard The worke, a month at least.
1642 C. Vernon Consid. Exch. 91 The principal causes which have hindred and retarded the due answering of the Kings Revenues and Debts.
b.2.b To defer, postpone, put off. rare.
1735 in Pope's Lett. Suppl. 11 He retarded his Edition of Mr. Cromwell's Letters till the Twenty-Second of March.
1820 Scott Monast. xvi, If we were now either to advance or retard the hour of refection beyond the time.
3.3 intr. To be delayed; to come, appear, or happen later; to undergo retardation.
1646 Sir T. Browne Pseud. Ep. 194 Putrefaction‥shall retard or accelerate according to the subject and season of the year.
1665 Phil. Trans. I. 38 The Comet advances‥towards the East, and‥retards towards the West.
1738 Ibid. XL. 312 The next Evening it retarded two Hours.
b.3.b To delay to do something. rare—1.
a 1732 Gay Tales, Apparition, Call loud on Justice, bid her not retard To punish murder.
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As a noun:<p><pre><code> 1.1 Retardation, delay. in retard, retarded, delayed; in the rear of.
1788 Jefferson Writ. 1859 II. 353 A single day's retard.
1865 Carlyle Fredk. Gt. xv. x. (1872) VI. 65 The rearward regiments‥are in painful retard.
1886 Ruskin Præterita I. iv. 132, I was far in retard of them in real knowledge.
2.2 retard of the tide or retard of high water, the interval between the moon's transit and the high water following upon this. Also ellipt.
1833 Phil. Trans. CXXIII. 19 The retard‥at Portsmouth appears to be intermediate between that at Brest and at London.
1845 Encycl. Metrop. V. 257* marg., Retard of high water upon the moon's transit.
1862 New Amer. Cycl. XV. 471 At Boston, this delay, which is called the retard, or age of the tide, is nearly 36 hours.
3.3 A device in a motor vehicle for retarding the ignition spark.
1932 Motoring Encycl. 10/3 The Bosch automatic advance and retard (Fig. 3) is a simple design for a stationary armature type of magneto.
1977 Hot Car Oct. 75/3 The old one is capped off still retaining the advance retard.
4.4 U.S. slang. A mentally retarded person.
1970 Time 23 Mar. 49 There are‥heroin addicts, Air Force and CIA mental retards and Broadway Indians doing a Broadway Snake Dance.
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~ Oxford English Dictionary Second Edition (CD-ROM v. 4.0 © Oxford University Press 2009)