unˈcouple, v.
[un-2 4 b. Cf. MDu. ontcoppelen, -copplen, Du. ontkoppelen.]
1. a. trans. To release (dogs) from being fastened together in couples; to set free for the chase.
| 13.. Guy Warw. (A.) 2512 A gret bore þai founden, y-wis, & hij uncopled her houndis. 1390 Gower Conf. I. 119 The houndes weren in a throwe Uncoupled and the hornes blowe. c 1410 Master of Game (MS. Digby 182) xiii, Þe firste bolde houndes hunteth alle manere of beestes þat his maister will vncouple hym to. a 1450 Knt. de la Tour (1868) 43 The houndes were uncoupeled on hem, and chaced and bote hem spitously bi the eeres and thies. 1555 Instit. Gentl. H vj b, Likewise huntyng in his kinde, as to fleshe a dogge, to vncupple houndes, to followe them [etc.]. 1576 Turberv. Venerie 102 They shall place their houndes in some faire place.., forbidding the varlet that he uncouple them not without their knowledge. 1600 Surflet Countrie Farme vii. xxv. 847 He must not vncouple any of his dogs; but onely marke the way that the Hart runneth. 1821 Scott Kenilw. xii, Ere we had uncoupled the hounds, he..turns bridle..and leaves us to hunt at leisure by ourselves. 1842 Mrs. Gore, etc. Fascination xi, Order the hounds to be uncoupled, and I will beat the underwood with three or four of the surest. |
b. absol. (Also in fig. use.)
| c 1386 Chaucer Monk's T. 512 He maked hym so konnyng and so sowple That longe tyme it was er tirannye Or any vice dorste on hym vncowple. c 1410 Master of Game (MS. Digby 182) xxxv, Þe herte houndes..þat before haue be ladde by somme forster or parker þedur as þei shull vncouple. 1596 Edward III, i. ii. 91 What, are the stealing Foxes fled and gone, Before we could vncupple at their heeles? 1599 Shakes. Mids. N. iv. i. 112 My Loue shall heare the musicke of my hounds. Vncouple in the Westerne valley. |
2. To unfasten, disconnect, detach.
| a 1533 Ld. Berners Gold Bk. M. Aurel. (1546) N n j b, How far is our vnderstandyng vncoupled for thy thoughtes. 1548 Udall, etc. Erasm. Par. John xiv. 87 b, That shall so couple you and vs together, that neyther lyfe nor death can vncouple vs. 1581 Mulcaster Positions xxxv. (1887) 124 Being so neare companions in linke, and not to be vncoupled in learning. 1685 Dryden Lucretius iii. 10 When our mortal frame shall be disjoyn'd, The lifeless Lump uncoupled from the mind, From sense of grief and pain we shall be free. 1786 Jefferson Writ. (1859) II. 23 Congress have desired those States to uncouple the grants, so that each may come into force separately. 1858 O. W. Holmes Aut. Break.-t. viii, Will nobody block those wheels, uncouple that pinion, cut the string that holds those weights? 1884 Harper's Mag. July 273/1 The locomotive is uncoupled from the cars. |
3. a. Biochem. To separate the processes of (phosphorylation) from those of oxidation.
| 1948 Jrnl. Biol. Chem. CLXXIII. 808 These results indicate that DNP [sc. dinitrophenol] reversibly uncouples phosphorylation from oxidation. 1977 D. E. Metzler Biochemistry vii. 366/1 Arsenate is said to uncouple phosphorylation from oxidation. |
b. Physics. To cause to cease to interact; to decouple (sense 2 a).
| 1980 Chem. in Brit. XVI. 456/2 This excited state may return to groundstate or undergo a chemical reaction or may uncouple two electron spins (intersystem crossing) to yield a triplet state. |
Hence unˈcoupled ppl. a.1; unˈcoupler: spec. in Biochem., any agent that causes the uncoupling of oxidative phosphorylation.
| 1687 Dryden Pal. & Arc. ii. 236 Th' appointed Place In which th' uncoupl'd Hounds began the Chace. 1705 Stevens ii, An Uncoupler, desuñidor. 1728 Chambers Cycl., Decouple, in Heraldry, the same as Uncoupled, i.e. parted or sever'd. 1803 Scott Cadyow Castle x, Steeds snort; uncoupled stag⁓hounds bay. 1954 Proc. Nat. Acad. Sci. XL. 919 Mitochondria suspensions taken from thyroxine-treated animals remain uncoupled. 1956 Science 22 June 1107/1 The factor specifically inhibits phosphorylation without affecting the oxidation of β-hydroxybutyrate and thus simulates the action of 2,4-dinitrophenol and other known uncouplers. 1976 Sci. Amer. June 44/3 Then we tried uncouplers: agents that allow electron transport to proceed but that in effect disconnect it from phosphorylation and thus from the ATP synthesis it usually accomplishes. 1979 Nature 8 Feb. 486/1 We have found that the rapid efflux of Ca2+ brought about by collapse of the membrane potential by uncouplers or antimycin A..is not affected by tetracaine. 1981 Plant Physiol. LXVIII. 1485/1 The light saturated rate of photosystem I-dependent electron transport..was increased by a high concentration of DCMU added to broken and uncoupled chloroplasts. |
______________________________
Add: 4. intr. Of a couple: to separate at the end of a relationship; to ‘split up’. Occas. refl. colloq.
| 1942 Berrey & Van den Bark Amer. Thes. Slang §360 Divorce,..uncouple. 1977 Washington Post 19 June k1/4 The pace is very fast, punctuated with the required moments of taut emotions when friends and lovers conspire and deceive, couple and uncouple. 1978 Chatelaine Dec. 42/1 Although a third of all marital partners uncouple themselves, 80{pcnt} will head back into marriage. 1989 Boston Globe 9 Mar. 15/5 Husband and wife would decide in advance which would control the fate of their biological merger if they uncouple. |