| 释义 |
react, v.1|riːˈækt|
[See re- 2 a and act v. Cf. F. réagir (18th c.), late L. reagĕre (5th cent.).]
1. a. intr. To act in return, or in turn, upon some agent or influence. Also without const.
Sometimes used loosely when previous action is merely implied or possible.
1644Digby Nat. Bodies xvi. 141 If fire doth heate water, the water reacteth againe..vpon the fire and cooleth it. 1724Swift Answer Misc. (1735) V. 21 Because, the Soul her Power contracts, And on the Brother Limb re-acts. 1771Wesley Wks. (1872) V. 233 God does not continue to act upon the Soul, unless the Soul re-acts upon God. 1831Macaulay Sp. in Ho. Comm. 5 July, Government and society are cause and effect—they re-act on each other. 1880McCarthy Own Times IV. l. 61 Applause reacts upon the orator.
b. spec. in Chem. of the action of reagents.
1797Encycl. Brit. (ed. 3) IV. 415/1 The nitrous acid soon..reacts on the other metals, and dissolves them. 1845G. E. Day tr. Simon's Anim. Chem. I. 359 Chyle of different qualities may react with varying energy on the lymphatic glands.
c. trans. To cause to react chemically or immunologically with or together.
1944[see adduct n.]. 1949[see oxo- 2 c]. 1962J. C. Wright Metallurgy in Nuclear Power Technol. v. 91 In the Degussa process fine beryl is reacted with excess lime at 1,500°C. 1963Listener 14 Mar. 459/2 A team of workers..showed that xenon and fluorine could readily be reacted together to produce xenon-tetrafluoride. 1971Nature 21 May 195/1 These, and several antisera previously made against Australasian marsupial sera, were reacted with a range of sera from Australasian and American marsupials in immunoelectrophoretic tests. 1972Sci. Amer. Aug. 34/1 It is fairly easy to react unsaturated molecules with a variety of chemical reagents.
2. intr. To act, or display some form of energy, in response to a stimulus; to undergo a change under some influence. Const. to (in recent use). Also, of a person: to respond; to behave in response to an event, a statement, etc.
1656tr. Hobbes' Elem. Philos. (1839) 393 Though all sense..be made by reaction, nevertheless it is not necessary that every thing that reacteth should have sense. 1856Kane Arct. Expl. II. v. 67 The less severe cases..are beginning to feel the influence of their new diet; but Wilson and Brooks do not react. 1882Vines tr. Sachs' Bot. 895 The tendency to expand is increased by darkness..: light has the contrary effect, and the one half always reacts more powerfully than the other. 1891F. Darwin in Nature 409 Plants may gain..various aptitudes for reacting to light and gravitation. 1913H. James Small Boy & Others xv. 212 What tenuity of spirit it argues that I should neither have enjoyed nor been aware of missing..a space wider than the schoolroom floor to react and knock about in. 1921G. B. Shaw Back to Methuselah p. xlviii, The assumption that he may safely cross Oxford Street in a state of unconsciousness, trusting to his dodging reflexes to react automatically and promptly enough to the visual impression produced by a motor bus. 1928E. O'Neill Strange Interlude i. 25 My heart pounding!..seeing Nina again!..how sentimental..how she'd laugh if she knew! and quite rightly..absurd for me to react as if I loved..that way. 1931― Haunted ii, in Mourning becomes Electra (1932) 251 Lavinia... I have a right to love! Orin (reacting as his father had—his face grown livid—with a hoarse cry of fury grabs her by the throat). You—you whore! 1953Times 13 May 3/5 Mr. Selwyn Lloyd said the Siamese Government..was reacting to this threat by taking precautionary measures on the north-eastern frontier. 1966Guardian 11 Aug. 8/2 Pictures not only of the member addressing the House..but of other members reacting to his speech. 1979Economist 28 Apr. 28/2 A firework lobbed by a demonstrator caused the police to react.
3. intr. To act in opposition to some force. Const. against.
1861M. Arnold Pop. Educ. France p. xx, I know that some individuals react against the strongest impediments. 1871Daily News 31 Jan., He..did all that lay in him to react against the cry, à Berlin.
4. intr. To move or tend in a reverse direction; to return towards a previous condition. spec. of share prices: to fall after rising.
1875Tennyson Q. Mary iv. iii. 246 Heaven help that this re-action not re-act Yet fiercelier under Queen Elizabeth. 1893Westm. Gaz. 29 Nov. 2/1 His father was a strong Wesleyan, and the son, as was natural, reacted towards the Church of England. 1896Daily News 5 Nov. 7/4 Silver reacted 2½, but rallied 13/4 on dealings. 1908Daily Chron. 10 Jan. 1/7 In one or two directions Stock Markets were again heavy, and prices further reacted. 1927Daily Tel. 22 Nov. 2 Cairn line reacted 9d and P. and O. fell 2. 1972Ibid. 29 Apr. 17/6 The shares reacted to 222p before rallying to 228p, a net loss of 2.
†5. trans.
a. To exercise in turn.
b. To drive back, to reflect. Obs.
1646Sir T. Browne Pseud. Ep. 386 The spirits of many..meeting no assimilables wherein to react their natures, must certainely anticipate such naturall desolations. 1678Cudworth Intell. Syst. i. v. 731 Every thing that suffered and reacted motion, especially polite bodies, as looking-glasses.
Hence reˈacting vbl. n. and ppl. a.
1611Florio, Reattióne, a reacting, or reaction. 1685J. Chamberlayne Coffee, Tea, & Choc. 60 The acting and re⁓acting which they have one upon another. 1833Chalmers Const. Man (1835) I. iv. 173 The actings and reactings that take place between man and man. 1871Morley Voltaire (1886) 5 A kind of reacting sympathy. 1896Allbutt's Syst. Med. I. 245 Some modification in the reacting tissue. |