| 释义 |
▪ I. latent, a.|ˈleɪtənt|
[ad. L. latent-em, pres. pple. of latēre to be hidden. Cf. F. latent.]
a. Hidden, concealed († rarely const. from); present or existing, but not manifest, exhibited, or developed. (The opposite of patent.)
latent ambiguity: in Law, a doubt as to the meaning of a document, not patent from the document itself, but raised by the evidence of some extrinsic and collateral matter (Wharton Law Lex. 1848). latent partner, one whose name does not appear as a member of a firm or company.
1616Bullokar, Latent, hiden, or secret. 1624Gataker Transubst., etc. 197 The pretence of a Church and Religion like to theirs in former ages canot..be defended... Some will haue it to haue beene latent and invisible for 800..yeers. 1651Baxter Inf. Bapt. 241 Though the Historicall part have some latent corruption in it. 1671J. Webster Metallogr. iii. 55 A metalline plastick principle latent in it. 1689T. Plunket Char. Good Commander Prol., New Necessities Will things produce, now latent from the wise. 1736Butler Anal. i. i. Wks. 1874 I. 26 We know not what latent powers and capacities they [brutes] may be endued with. 1757Burke Abridgm. Eng. Hist. Wks. 1842 II. 530 An exertion of a latent genius. 1849Macaulay Hist. Eng. i. I. 100 Under this apparent concord a great schism was latent. Ibid. v. 568 The meaning latent under this specious phrase. 1873Black Pr. Thule xv. 241 The latent force of character that underlay all her submissive gentleness. 1879Haddan Apost. Succ. iv. 80 Döllinger's expression, that the Episcopate was from the first latent in the Apostolate. 1913Act 3 & 4 Geo. V c. 20 §90 Any latent partner of a company whose estates have been sequestrated.
b. Of material things. ? Obs.
1646Sir T. Browne Pseud. Ep. iv. xiii. 223 That most insects are latent, from the setting of the 7 Starres. a1661Fuller Worthies (1840) III. 138 His admirable writings of mathematics are latent with some private possessors. c1690Scottow in Harper's Mag. Mar. (1883) 591/2 A snake which Lay Latent in the Tender Grass. 1700Dryden Ajax & Ulysses 172 The glitt'ring helm by moonlight will proclaim The latent robber. 1769Gray Ode for Music 3rd Air, Thy liberal heart..Shall raise from earth the latent gem To glitter on the diadem.
c. That is really but not evidently what is implied by the n.; disguised. rare.
1662J. Bargrave Pope Alex. VII (1867) 19 This latent nuntio gave over his fruitless design. 1725Pope Odyss. iii. 54 Then first approaching to the elder guest, The latent goddess in these words addrest. 1892Stevenson Across the Plains i. 26, I had been but a latent emigrant, now I was to be branded once more, and put apart with my fellows.
d. Med. and Biol. ‘Applied to diseases, the usual symptoms of which are not manifest, and to symptoms which do not appear under conditions in which they are natural’ (Syd. Soc. Lex. 1888); latent period, the period during which a disease lurks in the system before manifesting its presence; latent virus, a virus causing no apparent disease in a plant or animal, but capable of producing disease in another to which it is transmitted.
1684[see latic]. 1706Phillips (ed. Kersey) s.v. Cancer, Primitive Cancer, is that which comes of it self, and appears at first about the bigness of a Pea or Bean, causing an inward continual and pricking Pain; during which time it is call'd an Occult, Latent, or Blind Cancer. 1834J. Forbes Laennec's Dis. Chest (ed. 4) 97 The constant presence of a catarrhal affection of the lungs, either latent or manifest. 1837M. Hall Med. 143 Rubeola is unequivocally contagious. A latent period of from ten to fourteen days intervenes between exposure and the development of the febrile symptoms. 1886N.Y. Med. Jrnl. 4 Dec. 626/2 Heterophoria may, like hypermetropia, be partly or entirely latent. 1897Allbutt's Syst. Med. IV. 9 The foregoing train of symptoms being..known as those of ‘gouty dyspepsia’ or as ‘suppressed’, ‘anomalous’ or latent gout. 1931Phytopathology XXI. 593 A virus remaining latent or producing a mosaic in some varieties may cause a well-defined necrotic effect in others. 1937Science 20 Aug. 179 (title) A latent virus of lily. 1950K. M. Smith Introd. Study of Viruses ii. 17 We have seen already a good example of the ‘lighting up’ of a latent virus when discussing swine influenza... The virus is latent in its intermediate host, the swine lungworm, and to induce infection in the pig it must be rendered active by the application of a provocative stimulus. 1951Nature 30 June 1061/1 The presence of latent or ‘silent’ viruses in plants and other organisms is not, of course, new. 1954S. Duke-Elder Parsons' Dis. Eye (ed. 12) xxix. 483 In all types [of squint] if the fusion mechanism is well-developed and the defect slight, visual alignment may be maintained in normal circumstances by a continued effort of fusion: the squint is then latent and can only be made manifest when fusion is impossible (as by covering up one eye). 1962W. Carter Insects in Relation to Plant Dis. viii. 329 Latent viruses are often important components of virus complexes.
e. Physics. latent electricity: see quot. 1885. latent heat: see heat n. 2 c; so † latent caloric.
1816J. Smith Panorama Sci. & Art II. 334 Latent caloric may become sensible in a variety of ways. 1885Watson & Burbury Math. Theory Electr. & Magn. I. 83 The fluid of either kind in any electrified body in excess of that of the opposite kind is called the Free Electricity of the body, and the remaining fluids of the body, consisting of equal amounts of fluids of opposite kinds, together constitute what is called the Latent, Combined or Fixed Electricity of the body.
f. Bot. and Zool.
1787Families of Plants I. 263 The rudiments of eight anthers latent in the bottom of the flower. 1826Kirby & Spence Entom. IV. 348 Latent (Latens) when it [the post dorsolum] is covered by the mesothorax. 1856Henslow Dict. Bot. Terms, Latent, lying dormant till excited by some particular stimulus; as the adventitious buds occasionally developed in trees.
g. Photogr.
c1865J. Wylde in Circ. Sci. I. 157/2 The latent picture becomes developed. 1878Abney Treat. Photogr. iii. 18 The invisible image is frequently termed latent, an appellation which, though convenient, is yet open to some criticism.
h. Biol. latent period: a period between a stimulus and a response, esp. in a muscle or an irradiated individual. (See also sense d and latency 2 a.)
1877M. Foster Text Bk. Physiol. i. ii. 37 A phase antecedent to any visible alteration in the muscle..during which invisible preparatory changes are taking place in the nerve and muscle, is often called the ‘latent period’. 1926L. Hogben Compar. Physiol. viii. 140 The rate of conduction can be determined directly by observing the difference in the latent period of muscular contraction, when a nerve-muscle preparation is stimulated at points along the nerve separated by a measured distance apart. 1933O. Glasser Sci. of Radiol. xviii. 319 Should the criterion be the first reaction which can be observed under the microscope in the living cell, the latent period will be very short. 1947Radiology XLIX. 361/2 The incidence of bone tumors was approximately proportional to the dose administered, and the latent period—in no case less than about 200 days—increased gradually with decreasing dose. 1966McGraw-Hill Encycl. Sci. & Technol. VIII. 638/1 Between the stimulus and the first tension development there is a brief latent period of a few thousandths of the twitch duration.
i. Math. latent root: a scalar quantity λ which, when subtracted from each of the elements in the principal diagonal of a square matrix A, makes the determinant of the resulting matrix equal to zero (and so is a solution of the equation Ax = λx, where x is a column vector).
1883J. J. Sylvester in Phil. Mag. XVI. 267 It will be convenient to introduce here a notion (which plays a conspicuous part in my new theory of multiple algebra), viz. that of the latent roots of a matrix—latent in a somewhat similar sense as vapour may be said to be latent in water or smoke in a tobacco-leaf. If from each term in the diagonal of a given matrix, λ be subtracted, the determinant to the matrix so modified will be a rational integer function of λ; the roots of that function are the latent roots of the matrix; and there results the important theorem that the latent roots of any function of a matrix are respectively the same functions of the latent roots of the matrix itself: ex. gr. the latent roots of the square of a matrix are the squares of its latent roots. 1958R. V. Andree Sel. Mod. Abstract Algebra ix. 195 In quantum mechanics and elsewhere, the terms latent roots, proper value, eigenvalue, and eigenwerte are often used in place of characteristic root. 1968E. T. Copson Metric Spaces viii. 117 The condition..is known to imply that all the latent roots of A lie in {vb}z{vb} ‹ 1. Hence the latent roots of I - A lie in {vb}z - 1{vb} ‹ 1. Thus z = 0 is not a latent root of I - A, so that I - A is non-singular.
j. latent (finger-)print = latent n.
1923J. A. Larson Single Fingerprint Syst. i. 8 Take to your office all removable objects with visible or latent prints. Ibid. 9 Various powders, fumes, and solutions are recommended and have been used for the development and preservation of latent prints. 1937Discovery Feb. 56/2 When a latent print is discovered, the area can receive a more liberal fuming to yield the maximum contrast. The amount of time required for fuming a single latent image is variable. 1956‘E. McBain’ Cop Hater (1963) xix. 145 The tech crew dusted the latent fingerprints. 1962M. Procter Devil in Moonlight x. 102 ‘What's he expert on?’ ‘Latent fingerprints.’ Ibid. xiv. 145 What they call latent prints, not visible to the human eye. 1974G. F. Newman Price viii. 242 Latent prints brought out on the non-absorbent surfaces with grey powder for photographing.
k. Psychol. latent learning, learning that has taken place without conscious purpose and that is not manifested until there is a goal to be achieved.
1929H. C. Blodgett in Univ. Calif. Publ. Psychol. IV. 122 Do these drops in errors which come after the introduction of reward indicate that something to be called a latent learning developed during the non-reward period—a latent learning which made itself manifest after the reward had been presented? Ibid. 133 During the non-reward period, the rats were developing a latent learning of the maze which they were able to utilize as soon as reward was introduced. 1938R. S. Woodworth Exper. Psychol. vi. 137 ‘Latent learning’, i.e., learning that is not revealed by the animal's path through the maze, until food has been found in the food box. 1956E. R. Hilgard Theories of Learning (ed. 2) vi. 214 This second phase demonstrates genuine latent learning of the true path. 1957New Biol. XXIV. 123 If rats, not deprived of any primary bodily needs, are put in a maze, they explore it... If such rats are later trained to run from one part of the maze to another to get food, they learn this task more quickly than similar rats which have not previously experienced the maze. This consequence of exploration is called latent learning.
1968Chaplin & Krawiec Syst. & Theories Psychol. (ed. 2) vii. 277 Latent learning is hidden learning which goes on unobserved but which, under certain conditions, can be revealed in performance.
l. Sociol. latent function, a function which exists unrecognized within a social attitude or action and which will produce results that have not been foreseen.
1949R. K. Merton Social Theory i. 51 Latent functions..being those which are neither intended nor recognized. 1961M. Spiro in B. Kaplan Studying Personality ii. 108 Latent functions are those consequences which—whether intended or unintended—are not recognized by them [sc. members of a society].
m. Sociol. and Statistics. Applied to certain attributes, structures of relations, and the like (see quots. 1957).
1950P. F. Lazarsfeld in S. A. Stouffer Measurement & Prediction x. 362 (heading) The logical and mathematical foundation of latent structure analysis. Ibid., The latent structure approach to the treatment of itemized tests. 1952Goode & Hatt Methods in Social Res. xvii. 286 One alternative..was to abandon the factorial approach and in doing so abandon the concept of a latent-attitude continuum. Ibid. 295 Another problem posed by latent-structure analysis..is the fact that its computations are both arduous and complex. 1957Kendall & Buckland Dict. Statistical Terms 158 Latent structure,..a structure expressed in terms of variates or variables which are ‘latent’ in the sense of not being directly observable. Certain econometric relations (e.g. in terms of ‘utility’) are of this type. Ibid., Latent variable, a variable which is unobservable but is supposed to enter into the structure of a system under study, such as demand in economics or the ‘general’ factor in psychology. Unobservable quantities such as errors are not usually described as latent. 1961J. Rothenberg Measurement Social Welfare iv. xi. 290 The spatial arrangement of alternatives is a uni-dimensional scale of some single ‘latent attribute’ calibrated by the particular alternatives. 1966B. S. Phillips Social Res. xi. 176 Latent structure analysis may prove to be of particular value in bringing to light a systematic set of assumptions or propositions about the probabilistic relationships between manifest data and latent structures. 1968Lazarsfeld & Henry Latent Structure Analysis ii. 15 It is necessary to make some assumptions about the nature of what we called the ‘latent variable’. Ibid. iii. 47 Once a latent structure model has been specified, with accounting equations..relating the latent probabilities to the manifest probabilities, we must ask whether those equations can be solved uniquely.
Hence ˈlatently adv., in a latent manner, so as to be hidden or invisible; ˈlatentness, latency.
1651Raleigh's Ghost 103 Who would not affirm that a certain understanding..were invisibly and latently in the said things? 1660J. Durham Comm. Rev. xii. 531 Her latentnesse and inconspicuousnesse. 1684T. Burnet Theory Earth i. 285 Neither can we..judge..of what things the memory may be still latently conserv'd. 1837Whewell Hist. Induct. Sci. iv. v. I. 343 The lateral support..was supplied latently.
▪ II. latent, n.|ˈleɪtənt|
[f. the adj.]
A kind of fingerprint, invisible to the naked eye.
1923J. A. Larson Single Fingerprint Syst. ix. 186 Several latents were left at the house which had been burglarized. 1937Discovery 57/2 This method [of fingerprint detection] does not result in the destruction of the latent. 1939E. S. Gardner D.A. draws Circle (1940) iv. 48 ‘Any latents, Bob?’ the sheriff asked. 1973A. Hunter Gently French iii. 23 The recognisable latents were either Quarles' or off-record, probably innocent. |