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dynamic, a. and n.
(daɪ-, dɪˈnæmɪk: see dyna-)
[ad. F. dynamique (Leibnitz 1692. Dict. Acad. 1762), ad. Gr. δυναµικός powerful, f. δύναµις power, strength.]
A. adj.
1. Of or pertaining to force producing motion: often opposed to static.
1827D. Gilbert in Phil. Trans. CXVII. 26 Mr. Watt..assumed one pound raised one foot high for what has been called in other countries the dynamic unit. 1843–46Grove Corr. Phys. Forces (ed. 1) 13 A comparative view of the corpuscular and dynamic theories of heat. 1850Ibid. (ed. 2) 74, I have used..the terms dynamic and static to represent the different states of magnetism. 1847J. Dwyer Princ. Hydraul. Engineer. 94 The horse's power is principally used by Engineers in this country as a Dynamic unit. 1855H. Spencer Princ. Psychol. (1872) II. vi. xi. 138 We find light producing a dynamic effect..in those molecular re-arrangements which it works in certain crystals. 1860Tyndall Glac. ii. xix. 331 According to the dynamic view..heat is regarded as a motion. 1881Armstrong Address Brit. Assoc. in Nature No. 619. 449 Such is the richness of coal as a store of mechanical energy that a pound of coal, even as used in the steam-engine, produces a dynamic effect about five times greater than a pound of gunpowder burnt in a gun.
2. Of or pertaining to force in action or operation; active.
1862Tyndall Mountaineer. i. 6 What would man be without Nature? A mere capacity, if such a thing be conceivable alone; potential, but not dynamic. 1863― Heat v. 137 While in the act of falling, the energy of the weight is active. It may be called actual energy, in antithesis to possible, or..dynamic energy, in antithesis to potential. Ibid. 138 As potential energy disappears, dynamic energy comes into play.
3. transf. and fig.
a. Active, potent, energetic, effective, forceful.
1856Emerson Eng. Traits, Lit. Wks. (Bohn.) II. 105 Their dynamic brains hurled off their words, as the revolving stone hurls off scraps of grit. 1876Geo. Eliot Dan. Der. i. i, What was the secret of form or expression which gave the dynamic quality to her glance? 1878Lecky Eng. in 18th C. I. i. 14 It [Greek intellect] has been the great dynamic agency in European civilisation.
b. Opposed to static.
1876C. P. Mason Eng. Gram. (ed. 21) 117 (To borrow a metaphor from mechanics) the adjective is a static attribute, the verb is a dynamic attribute.
4. Of, according to, or pertaining to the science of dynamics: as the dynamic theory of the tides.
1838–51Nichol Archit. Heav. (ed. 9) 196 A sure dynamic theorem. 1891E. Peacock N. Brendon II. 416 The dynamic laws which cause a pump to act.
5. Med.
a. Functional, in contradistinction to organic; as in dynamic disease.
b. With Hahnemann and his followers: Of the nature of some immaterial or ‘spiritual’ influence.
†c. Attended with a morbid increase of vital action, sthenic (obs.).
dynamic school: a name given to the Stahlians, or followers of Stahl, as attributing the vital phenomena to the operation of an internal force or power acting for the most part independently of external causes. (Syd. Soc. Lex.)
[1829see adynamic.] 1834Good's Study Med. (ed. 4) IV. 272 Dr. Stoker..has divided dropsies into two kinds, dynamic and adynamic. 1855J. R. Reynolds Dis. Brain ix, The simple fact of convulsions is proof of dynamic (functional) disease. 1881J. G. Glover in Encycl. Brit. XII. 128/1 (Homœopathy), Underlying all his [Hahnemann's] system..was the idea that the causes of disease were impalpable, immaterial, spiritual, dynamic. 1882Med. Temp. Jrnl. I. 114 A dynamic narcosis of the ultimate fibres of sensation.
6. In the Kantian philosophy: Relating to the reason of existence of an object of experience.
dynamic relations, the relations between objects as forming parts of one connected experience: viz. the relations of substance and accident, of cause and effect, and of substances acting upon each other. dynamic category, a category that expresses one of the dynamic relations. dynamic synthesis, a synthesis which is guided by the dynamic categories.
7. Relating to the existence or action of some force or forces; applied esp. to a theory that accounts for matter, or for mind, as being merely the action of forces: see dynamism 1.
dynamic theory of Kant, a theory according to which matter was conceived to be constituted by two antagonistic principles of attraction and repulsion.
1817Coleridge Biog. Lit. I. ix. 150 We had both equal obligations to the polar logic and dynamic philosophy of Giordano Bruno.
8. Mus. Of, pertaining to, or indicating the volume of sound from a musical instrument or in a musical performance. Also transf.
1893J. S. Shedlock tr. Riemann's Dict. Mus. 226/1 The natural dynamic shading of a musical phrase is therefore crescendo..and diminuendo... Dynamic and agogic shadings must be used with economy. 1931G. Jacob Orchestral Technique iii. 29 It is excellent as a bass-strengthener, however, in dynamic ranges of mf and upwards. 1941B.B.C. Gloss. Broadc. Terms 10 Dynamic range, range of intensities within which the volume of a programme fluctuates. 1948Penguin Music Mag. June 129 Fearless attack, great volume, and subtle dynamic changes.
9. dynamic braking = electric braking; dynamic equator (see quot. 1883); dynamic metamorphism (also dynamical m.) Geol., metamorphism produced by mechanical forces; dynamic pressure, the pressure in a fluid that is due to its motion.
1930Engineering 24 Jan. 105/1 Driven by two 100 h.p. mill-type motors..equipped with solenoid and dynamic braking. 1950Ibid. 22 Dec. 528/2 Slip-ring induction motors with dynamic braking.
1883Encycl. Brit. XVI. 165/1 The line connecting all the points where the magnetic intensity is least is called the dynamic equator.
1893Jrnl. Geol. I. 854 The dynamic metamorphism of the eruptive rocks occurring in it. 1965A. Holmes Princ. Phys. Geol. (ed. 2) viii. 170 Since the main process is dynamic, slate is said to be a product of dynamic metamorphism.
1919A. B. Eason Flow & Measurem. Air & Gases ix. 163 Threlfall..mentions tests made upon a Pitot tube in which..there was a large suction effect, and..the difference between the static and dynamic pressures was of the form H = k(u)n, where n was greater than 2. 1949O. G. Sutton Sci. of Flight ii. 36 The dynamic pressure of the flow..is the pressure felt on the nose of a body at the point where the impinging stream is actually brought to rest. 1970A. C. Kermode Flight without Formulae 43 A fluid can exert pressure for two reasons: first because of its movement... The pressure due to movement we will call dynamic pressure.
B. n.
1. = dynamics, q.v.
1873Clifford Syllabus of Lectures in Math. Papers (1882) 516 The science which teaches under what circumstances particular motions take place..is called Dynamic..It is divided into two parts, Static..and Kinetic. 1878― (title) Elements of Dynamic: an Introduction to the Study of Motion and Rest in Solid and Fluid Bodies.
2. = Dynamic theory: see A. 7.
1884tr. Lotze's Metaph. 305 As Kant does in the course of his ‘Proof’ of this ‘Precept No. 1’ of his ‘Dynamic’.
3. Energizing or motive force.
1894H. Drummond Ascent of Man 270 The Struggle for Life, as life's dynamic, can never wholly cease. 1896Advance (Chicago) 16 July 80/1 There is lack of dynamic. There is lack of direct soul-changing power.
4. Mus. = dynamics 3.
[1884H. Riemann (title) Musikalische Dynamik und Agogik.] 1959D. Cooke Lang. Music iii. 159 The minor system, soft dynamic, and slow tempo.
Add:[A.] [8.] dynamic range, a range of acceptable or possible volumes of sound, esp. the range of volumes occurring in the course of a piece of music, performance, programme, etc.; spec. the ratio of the largest to the smallest intensity of sound that can be reliably transmitted or reproduced by a particular sound system.
1917G. B. Shaw How to become Mus. Critic (1960) 294 Sir Thomas Beecham..seems to have no conception of the dynamic range of Mozart's effects. 1949[see transduce v. 1]. 1967DB Nov. 16/2 This technique can improve the dynamic range of the recorder up to 6 dB with attendant low distortion. 1980Audio Jan. 52/1 Even these fine recordings are too often marred by the presence of record surface noise and restrictions on the dynamic range that could be captured on and retrieved from a vinyl disc.
▸ dynamic pricing n.‹dynamic adj. + pricing n., after Swedish dynamiska prisbildning (G. Myrdal Prisbildningsproblemet och föränderligheten (1927) i. 1) Business the varying of a product's price to reflect changing market conditions; esp. the charging of higher prices at times of greater demand, in more affluent areas, etc.
1929E. Lindahl in Econ. Jrnl. 39 89 There are two quite distinct problems which are caused by the dynamic conditions of the economic life, depending on the point of view from which *dynamic pricing is analysed. 1964A. Isaacs & R. E. Slesinger Business, Govt. & Public Policy 178 Consumer free choice, dynamic pricing, and freedom to contract are fundamentals of the enterprise approach. 2000Washington Post 27 Sept. a1/1 It was the first major Web test of a strategy called ‘dynamic pricing’, which gauges a shopper's desire, measures his means and then charges accordingly. |