variable, a. and n.
(ˈvɛərɪəb(ə)l)
Forms: 4– variable (5–6 varri-, 6 Sc. vareable), 5, Sc. 6, -abill, Sc. 6 -abil (warieabill), 5–6 varyable, 6 -abul, 5 uaryabyl, veryabyll.
[a. OF. variable (F., Sp., and Prov. variable, Pg. variavel, It. variabile), ad. L. variābilis, f. variāre to vary.]
A. adj.
1. Liable or apt to vary or change; (readily) susceptible or capable of variation; mutable, changeable, fluctuating, uncertain. a. Of the course of events, the state of things, etc.
| c 1397 Chaucer Lack Stedf. 8 What made this worlde to be so variable But louste þat folke haue in discencion? c 1400 Rom. Rose 5424 In a state that is not stable, But chaungynge ay and variable. 1448–9 J. Metham Wks. (E.E.T.S.) 54 Thy uaryabyl squel,..O fortune! brent myght be With Pluto in helle. 1483 Caxton Cato g iiij, For the goodes of thys worlde been varyable; now one is ryche and now poure. 1509 Hawes Past. Pleas. 51 They nothing thynke on fortune var[i]able. a 1548 Hall Chron., Hen. VI (1550) 34 The Englyshe affaires..began to wauer, and waxe variable. 1609 Holland Amm. Marcell. 119 Some joining in skirmish with the enemies, fought with variable event. 1610 ― Camden's Brit. 696 They had continued a doubtfull and variable fight a great part of the day. |
b. Of feeling, conduct, etc.
| c 1480 Henryson Orpheus & Eur. 287 Quhat art thou, lufe,..To sum constant, till othir variabil. 1555 Eden Decades (Arb.) 114 So variable and vnconstant is the nature of man. 1592 Shakes. Rom. & Jul. ii. ii. 111 O sweare not by the Moone,..Least that thy Loue proue likewise variable. 1596 ― Merch. V. ii. viii. 13, I neuer heard a passion so confusd, So strange, outragious, and so variable. 1667 Milton P.L. xi. 92 His heart I know, how variable and vain Self-left. 1849 Ruskin Sev. Lamps vii. §7. 191 The decorations..might be made subjects of variable fancy. 1862 H. Spencer First Princ. i. v. §29 (1875) 102 There begins to fade from the mind the conception of a special personality to whose variable will they were before ascribed. |
| Comb. 1618 Bolton Florus iv. iii. (1636) 293 While Antonius, variable-witted,..takes upon him to be a king. |
c. In miscellaneous applications.
| 1509 Barclay Shyp of Folys (1874) I. 126 By hir iyen clowdy and varyable vysage. 1576 Fleming Panopl. Epist. 442 These beautifull shapes,..not varriable in time, not withering throughe the heate of the sunne. 1590 Spenser F.Q. iii. vi. 38 For formes are variable and decay, By course of kind, and by occasion. 1609 Wibarne New Age Old Names To Rdr. A 4 b, If I haue omitted something in a matter so variable. 1703 Maundrell Journ. Jerus. (1732) 63 Our Course variable between East and South. 1711 Addison Spect. No. 98 ¶1 There is not so variable a thing in Nature as a Lady's Head-dress. 1832 Lewis Use & Ab. Pol. Terms Introd. 7 The variable meaning of a word. 1850 M{supc}Cosh Div. Govt. ii. i. (1874) 78 This production of change is not variable or capricious, but follows certain fixed laws. 1884 tr. Lotze's Logic 388 Events, which..depend at once on constant and on variable conditions. |
| absol. 1872 Bagehot Physics & Pol. (1876) 32 We overlook and forget the constant while we watch the variable. |
2. a. Of persons: Apt to change from one opinion or course of action to another; inconstant, fickle, unreliable.
| 1387 Trevisa Higden (Rolls) I. 357 Þe men beeþ variable and vnstedefast, trecherous and gileful. 1393 Langl. P. Pl. C. xix. 69 Somme of ows [are] sothfast and some variable. 1402 Hoccleve Min. Poems 78 Al-be-hyt that man fynde o woman nyce, In-constant, recheles, or varriable. 1474 Caxton Chesse ii. iii. (1883) 37 So that they be not founde..for enuye variable. a 1542 Wyatt in Tottel's Misc. (Arb.) 37 My word nor I shall not be variable, But alwaies..firme and stable. a 1578 Lindesay (Pitscottie) Chron. Scot. (S.T.S.) I. 135 The popularie..ar so warieabill and faccell. 1643 Baker Chron. (1653) 504 Lydington was..a man of the greatest understanding,..but very variable. 1708–9 Pennsylv. Hist. Soc. Mem. X. 313, I am very sensible he is a variable man, and not..to be entirely depended on. 1711 Addison Spect. No. 162 ¶5 One of the most variable Beings of the most variable Kind. 1808 Scott Marm. vi. xxx, Uncertain, coy, and hard to please, And variable as the shade By the light quivering aspen made. |
| transf. 1484 Caxton Curiall ij b, Them whom fortune the variable hath most hyely lyfte up and enhaunsed. a 1548 Hall Chron., Hen. VI, 110 b, King Charles did politiquely consider, what a variable lady Fortune was. |
b. Const.
in (words, actions, etc.).
| 1429 Pol. Poems (Rolls) II. 145 In thy behestes be nat variable. a 1513 Fabyan Chron. vii. (1811) 544 See you not howe varyable the kynge is in his wordis? 1547 Boorde Introd. Knowl. 214 In vsyng my rayment I am not varyable. 1562 W. Bullein Bulwarke, Bk. Vse Sickmen 55 Bee not variable in Religion. 1623 Jas. I in Ellis Lett. Ser. i. III. 139 He is in this busienesse..as variable and uncertaine as the Moone. |
† c. Liable to alter or turn
from (or
of) a purpose, etc.
Obs.| c 1400 Beryn 752 No mervell is, þouȝe Rome be som what variabill Fro honour & fro wele. 1412–20 Lydg. Chron. Troy iv. 5120 Þei wil holde stable, And finally nat be variable From þe ende, platly, þat þei make. c 1450 Cov. Myst. (Shaks. Soc.) 216 If we fynde hym varyable Of his prechynge that he hath tawth. 1493 Petronylla 21 (Pynson), From hir entent nat founde variable. |
3. a. Of the weather, seasons, etc.: Liable to vary in temperature or character; changeable.
| c 1480 Henryson Test. Cres. 150 The seuin Planetis..hes power..To reull..Wedder and wind, and coursis variabill. 1631 Gouge God's Arrows v. §15. 428 Peace is not like the immoveable mountaines, but rather like to the variable skie. 1722 De Foe Plague (Rtldg.) 14 The Weather was temperate, variable and cool enough. 1797 Encycl. Brit. (ed. 3) XVIII. 493/2 The great sunshine heats of Florence, which are too variable and undetermined. 1808 Med. Jrnl. XIX. 569 The weather..was very variable, but upon the whole mild. 1854 Poultry Chron. I. 288 Exposed entirely to the vicissitudes of our ever-variable climate. |
b. Of wind or currents: Tending to change in direction; shifting.
| 1665 Boyle Occas. Refl. iii. i. (1848) 146 As variable as the Wind. 1720 De Foe Capt. Singleton xiii. (1840) 229 We had the wind variable. 1774 Goldsm. Nat. Hist. I. 340 He who has been taught to consider that nothing in the world is so variable as the winds. 1832 H. T. De la Beche Geol. Man. 95 There is a tendency of the surface waters to the S.E., being variable in winter. 1840 R. H. Dana Bef. Mast xxv. 84 The wind shifted and became variable. 1854 Tomlinson Arago's Astron. 185 Much less regular in the temperate regions, they are called variable winds. |
c. Of a star: That varies periodically in respect of brightness or magnitude.
| 1788 Encycl. Brit. (ed. 3) II. 471/2 marg., Of the variable stars. 1854 Brewster More Worlds i. 7 It appears and disappears like a variable star, shewing in painful succession its spots of light and of shade. 1880 A. Giberne Sun, Moon & Stars 239 There are numbers of stars called Variable Stars, the light of which is constantly changing, now becoming more, now becoming less. |
d. Biol. Liable to deviate from a type; admitting of such deviation. (
Cf. variation 10.)
| 1859 Darwin Orig. Species v. 149 Beings low in the scale of nature are more variable than those which are higher. 1877 Conder Basis of Faith v. 231 Species, it has been well said, are ‘variable, but not mutable’. 1880 Wallace Island Life 59 It is now very easy to understand how, from such a variable species, one or more new species may arise. |
† 4. a. Characterized by variation or diversity; differing, diverse, various.
Obs.| 1432–50 tr. Higden (Rolls) I. 239 The peple wente furthe to mete the victor with variable [L. varia] gladdenesse. 1509 Hawes Past. Pleas. xvi. (Percy Soc.) 61 For musike doth sette in all untye The discorde thynges whiche are variable. 1539 Act 31 Hen. VIII, c. 14 By occasion of variable and sundrie opinions..great discorde..hathe arrisen. 1576 Fleming Panopl. Epist. p. iii, Flowers..delightsome to the eye, in consideration of their variable colours. 1601 Holland Pliny II. 372 The variable transformations of Proteus. 1613 Purchas Pilgrimage (1614) 167 It were a worke..tedious to the Reader, to recite the variable opinions of Chronologers..about these points. |
† b. Different
from something.
Obs.—1| 1509 Barclay Shyp of Folys (1570) 167 Thy visage chaunging by lookes manifolde:..Sometime as lead, from death scant variable. |
† c. Variegated.
Obs.—1| 1553 Eden Treat. New Ind. (Arb.) 16 Of the coloure of boxe, somwhat variable and as it wer chekered. |
† 5. Of varying ownership.
Obs.| 1549 in Leges Marchiarum (1705) 80 The Land variable, common of both the People, called the Debateable Ground, which lieth between the West Marches of England and Scotland. Ibid. 81 The said Variable Ground. |
6. a. Susceptible or admitting of increase or diminution, not remaining the same or uniform, in respect of size, number, amount, or degree.
| 1607 Topsell Four-f. Beasts 94 His belly is variable, now great, now small like an Oxes. 1804 Med. Jrnl. XII. 496 They are sold at a more reduced price, about 9s. per dozen; this, however variable,..leaves the money saved proportionably the same. 1815 J. Smith Panorama Sci. & Art II. 114 The pressure of the atmosphere is variable. 1858 Lardner Handbk. Nat. Phil. 281 When the quantity of heat necessary to raise a body one degree is different in different parts of the scale, the specific heat is said to be variable. 1882 Minchin Unipl. Kinemat. 27 If a point, P, moves round a circle with a velocity either constant or variable. |
b. Of quantity, number, etc.: Liable to vary.
| 1710 J. Harris Lex. Techn. II, Variable Quantities, in Fluxions, are such as are supposed to be continually increasing or decreasing; and so do by the motion of their said Increase or Decrease Generate Lines, Areas or Solidities. 1743 Emerson Fluxions 223 If any one of the variable Distances..be called x. 1763 ― Meth. Increments 41 Multiply the given increment by the next preceeding value of the variable quantity. 1801 Encycl. Brit. Suppl. II. 740/1 The abscisses and ordinates of an ellipsis, or other curve line, are variable quantities. 1828 Stark Elem. Nat. Hist. II. 374 A sucker composed of a variable number of scaly pieces. 1884 Bower & Scott De Bary's Phaner. 254 Small bundles, the number of which is variable. |
c. spec. (See
quot.)
| 1829 Hand-bk. Nat. Philos., Hydrost. viii. 2 (L.U.K.), Some springs, called variable or reciprocating,..discharge a much smaller quantity of water for a certain time, and then give out a greater quantity. |
d. variable cost (see
quot. 1974).
| 1953 [see prime cost s.v. prime a. 9 a]. 1967 A. Battersby Network Analysis (ed. 2) xii. 200 There are other cases which more closely resemble the variable-cost control, as when the number of men allocated to a job is variable and governs duration. 1969 D. C. Hague Managerial Economics i. 15 The remainder of total cost is made up of those costs that do vary with output—with what are therefore known as variable costs. 1974 Terminol. Managem. & Financial Accountancy (Inst. Cost & Managem. Accounts) 24 Variable cost, a cost which, in the aggregate, tends to vary in direct proportion to change in the volume of output or turnover. |
7. a. That may be varied, changed, or modified; alterable.
| 1597 Hooker Eccl. Pol. v. lxii. §14 What if the minister's vocation be..not a ceremony variable as times and occasions require? 1611 Bible Hab. iii. 1 marg., According to variable songs or tunes. 1875 Knight Dict. Mech. 2690 Variable Cut-off, one actuated from the governor, so as to be brought into action according to the load on the engine. 1887 Pall Mall G. 5 Nov. 7/1 The permanent taxes..will be variable only by regular Act. |
b. Gram. Capable of inflexion.
8. Nat. Hist. In specific names, as
variable cod,
variable hare,
variable ixalus,
variable jacana,
variable lemur,
variable maple,
variable mole,
variable rail,
variable tanager,
variable toad.
| 1862 Chambers's Encycl. III. 642/2 [The] Dorse..of the same genus with the cod..; its colour is more variable, from which it has received the name of *Variable Cod. |
| 1896 tr. Boas' Text Bk. Zool. 529 The Polar or *Variable Hare (Lepus timidus or variabilis)..is white during winter in the colder regions. |
| c 1880 Cassell's Nat. Hist. IV. 366 The *Variable Ixalus of Ceylon is..very variable in its coloration. |
| 1785 Latham Gen. Syn. Birds III. i. 244 *Variable Jacana (Parra variabilis). |
| 1896 H. O. Forbes Handbk. Primates I. 68 The Ruffed or *Variable Lemur derives its name from the remarkable variability of its external markings. |
| 1833 Penny Cycl. I. 78/1 Acer heterophyllum, the *variable maple... This is the plant sold in the English nurseries under the name of A. creticum. |
| 1776 P. Brown Illustr. Zool. 110 *Variable Mole. 1781 Pennant Hist. Quad. II. 485 Variable Mole;..color of the hair on the upper part of the body varied with glossy green and copper-color. |
| 1824 Stephens in Shaw Gen. Zool. XII. i. 198 *Variable Rail (Rallus varians). Brown Rail spotted and striated with black and white, with the body beneath and eyebrows cinereous or griseous. |
| 1783 Latham Gen. Syn. Birds II. i. 234 *Variable Tanager..: general colour of the plumage green, very glossy and variable. |
| c 1880 Cassell's Nat. Hist. IV. 360 The *Variable, or Green Toad, found in France, has hind limbs and feet nearly as large as those of the Frog. |
9. Special collocations.
a. In
attrib. use, as
variable-area,
variable-length,
variable-reluctance,
variable-speed.
| 1920 Flight XII. 5/1 Variable area or variable camber wings—or other means for reducing the landing speed of a machine. 1957 Manvell & Huntley Technique Film Music iii. 171 This optical wedge is caused to oscillate over a light slit by the motion of the pendulums, producing a variable-area type of sound-track. 1959 E. M. McCormick Digital Computer Primer viii. 119 These difficulties are avoided in many business computers by organizing the storage to accommodate variable-length records. 1970 Computers & Humanities IV. 327 The data fields of the customer's data base in variable-length capability. 1980 C. S. French Computer Sci. xi. 60 Variable length records mean difficulties for the programmer but better utilisation of storage. |
| 1959 W. S. Sharps Dict. Cinematogr. 138/1 A variable-reluctance microphone is a microphone which depends for its operation on variations in the reluctance of a magnetic circuit. |
| 1875 Knight Dict. Mech. 2691 Olmsted's Variable-Speed Pulley. Ibid., Variable-speed Wheel, a contrivance for obtaining alternately accelerated and retarded circular motion. 1978 P. Griffiths Conc. Hist. Mod. Music viii. 116 Cage went further and created..his Imaginary Landscape no. 1, in which musicians have to perform with frequency recordings on variable-speed turntables. 1984 B. Francis AA Car Duffer's Guide 67/2 A variable-speed fan is provided to boost the air-flow throughout the car's interior at low speeds. |
b. variable geometry, a configuration of component parts that can be varied;
spec. in
Aeronaut. = variable sweep below;
freq. attrib.;
variable-mu adj. (
Electronics), (of a valve) having an amplification factor that can be varied;
variable-pitch adj., of or pertaining to
† (
a) a propeller in which the blades are shaped so that the pitch varies along their length (see
quot. 1912) (
obs.); (
b) a propeller, fan, etc., in which the angle of the blades with respect to the direction of air flow can be adjusted,
esp. while they are in motion;
variable sweep (
Aeronaut.), sweep (sense 15) that can be varied during flight according to requirements;
usu. attrib.| 1957 Jrnl. Brit. Interplanetary Soc. XVI. 166 The design characteristics of such gliders may include..variable geometry lifting surfaces, to be very thin at high speeds and to have good lift properties at landing. 1963 Times 10 June 10/1 He believed that variable geometry would give a better aircraft. 1969 Sci. Jrnl. Apr. 48/1 The wing surface [of a bat's wing] is an elastic membrane of skin stretched between the four long fingers, with at least 11 movable joints in each wing. This very variable geometry permits a high degree of manoeuvrability and control. 1970 New Scientist 30 July 236 (caption) These drawings show the variable geometry of the air intake on the Olympus 593-3B engine. 1977 P. Way Super-Celeste 39 The rival to the Super-Celeste, the variable geometry wing F-24, was airborne again. |
| 1930 Ballantine & Snow in Proc. IRE XVIII. 2102 (heading) Reduction of distortion and cross-talk in radio receivers by means of variable-mu tetrodes. 1962 [see mu 2]. 1971 E. N. Lurch Fundamentals of Electronics (ed. 2) v. 143 The tube employing this special grid is termed cutoff, supercontrol, or variable-mu. |
| 1912 Ledeboer & Hubbard tr. Duchêne's Mech. of Aeroplane vii. 197 M. Drzewiecki, with the idea of getting the maximum efficiency out of every part of the propeller, varies the pitch at each point so that the actual angle of incidence is everywhere the optimum angle. Propellers of this kind are known as variable-pitch propellers, and are consequently no longer true screws. 1918 W. H. Berry Aircraft in War & Commerce vii. 91 Worked in combination with a variable pitch propeller the gearbox would allow the pilot a range in power and speed. 1919 H. Shaw Text-bk. Aeronaut. xi. 147 In the variable pitch type, the blade angle is varied continuously from the hub outwards in such a way that the slip column of air is forced backwards with a velocity which is uniform throughout. 1952 [see static thrust s.v. static a. 7]. 1971 Daily Tel. 4 Nov. 3 (Advt.), Variable pitch engine cooling fan. Large range to fit most popular cars. 1974 Encycl. Brit. Micropædia I. 375/1 Additional features have been engineered into variable-pitch propellers; first, the ability to feather..a propeller on an engine stopped in flight. |
| 1954 Economist 11 Sept. 12/3 Variable sweep. After take-off with wings only partially swept, means are provided to sweep them back more sharply in flight. Strictly experimental. 1965 New Scientist 22 Apr. 217/1 The development of the variable-sweep wing in collaboration with the French might lead to a load-carrier of outstanding performance. 1966 Economist 22 Jan. 330/1 Massive, variable-sweep aircraft whose wings pivot around stanchions as thick as tree-trunks. 1978 D. Küchemann Aerodynamic Design of Aircraft iv. 120 E. von Holst flew models with various arrangements of variable sweep. |
B. n. 1. a. Math. and
Phys. A quantity or force which, throughout a mathematical calculation or investigation, is assumed to vary or be capable of varying in value.
Cf. A. 6 b and
constant n.| 1816 tr. Lacroix's Diff. & Int. Calculus 4 The limit of the ratio..will be obtained by dividing the differential of the function by that of the variable. 1862 Draper Intell. Devel. Europe (1865) 173 In some mathematical expression containing constants and variables. 1882 Minchin Unipl. Kinemat. 238 In this case ϕ will also be a potential (or flow) function of the new variables (ξ, η). |
b. Computers. A data item that can take on more than one value during or between programs and is stored in a particular designated area of memory; the area of memory itself; (also
variable name) the name referring to such an item or location.
| 1837 C. Babbage in B. Randell Origins Digital Computers (1973) 23 The number of variables which can be contained within the store will depend on the length of the rack. 1843 Scientific Mem. III. 666 We have..written Variable with a capital letter when we use the word to signify a column of the engine, and variable with a small letter when we mean the variable of a formula. 1957 [see subscript n. 2 b]. 1967 Beckett & Hurt Numerical Calculations & Algorithms i. 23 Variable names are usually limited in length because they must be coded as numbers and space is required to store these numbers... The number of characters used to define a variable is arbitrary, provided that it does not exceed a given maximum. 1972 Bergman & Bruckner Introd. Computers & Computer Programming ix. 288 [In FORTRAN] the data locations are divided into constants and variables... Variables are locations into which we may read numbers or place (store) numbers at execution time. 1975 H. Katzan Introd. Computer Sci. v. 108 The names hours, rate, and pay are variables... A variable is an identifier that names a data item. 1979 Sci. Amer. Dec. 85/1 In programming languages a variable is not an item of data but a label for a location in the memory of the computer. The value of a variable at any moment is the information currently stored there. 1981 W. S. Davis Computers & Business Information Processing xiii. 234 A FORTRAN variable consists of from one to six letters or digits, the first of which must be a letter. 1982 Cooper & Clancy Oh! Pascal! i. 10 The variables that computers use are like the memory keys of hand calculators—they store values... Variables can hold different types of values, including integers.., characters.., or even logical values. |
c. Logic. A symbol whose exact meaning or referend is unspecified, though the range of possible meanings usually is.
| 1910 Whitehead & Russell Principia Mathematica I. i. 4 In mathematical logic, any symbol whose meaning is not determinate is called a variable. Ibid., If a statement is made about ‘Mr A and Mr B’, ‘Mr A’ and ‘Mr B’ are variables whose values are confined to men. 1937, etc. [see open a. (adv.) 11 j]. 1939 Jrnl. Philos. XXXVI. 702 Whereas the singular existence statement calls the alleged existent by name, e.g., ‘Pegasus’, the general existence statement does not; the reference is made rather by a variable ‘x’, the logistical analogue of a pronoun ‘which’, ‘something which’. 1954 A. J. Ayer Philos. Ess. ix. 216 The range of our ontological commitments may..be reduced by our ability to recast some of our existential statements in such a way that variables which take a certain type of value disappear from them. 1969 Feys & Fitch Dict. Symbols Math. Logic 6 In interpreting a formalized language it is usual to specify the respective ranges of the various variables of the language. 1978 S. Haack Philos. Logics iv. 39 In general, prefixing a quantifier binding one of its free variables to an open sentence with n free variables yields an open sentence with n—1 free variables. |
2. a. A variable or shifting wind;
spec. in
pl. (see
quots. 1857, 1867).
| 1846 A. Young Naut. Dict. 349 The meeting of the two opposite currents [of wind] here produces the intermediate space called the calms or variables. 1857 Tomes Americ. in Japan i. 31 The Variables, which are found South of the border of the South-east Trades. 1867 Smyth Sailor's Wordbk. 710 Variables, those parts of the sea where a steady wind is not expected. |
b. A variable star. (See A. 3 c.)
| 1868 Lockyer Elem. Astron. 21 Among the acknowledged variables β Persei is perhaps the most interesting. 1880 Athenæum 11 Sept. 341/1 The period of this interesting variable is a little less than five days. |
3. Something which is liable to vary or change; a changeable factor, feature, or element.
| 1846 Grote Greece ii. xxi. (1862) II. 229 The beginning and the end are here [in the Odyssey] the date in respect to epical genesis, though the intermediate events admit of being conceived as variables. 1865 Martineau in Theol. Rev. 670 A changing scene with the variables of which he is in immediate contact. 1881 H. H. Gibbs Double Standard 13 Uniformity, and therefore the removal of those variables which must be an encumbrance to commerce. |