[ad. L. curv-us bending, bent, curved, crooked.]
A. adj. Curved. Now rare.
1571. Digges, Pantom., II. xiii. N iij b. Suche playne Superficies as are enuironed with curue lynes.
1665. Phil. Trans., I. 107. The Tail is curve.
1716. Cheyne, Philos. Princ. Relig., I. 95. Partly terminated with plain, and partly with curve surfaces.
1755. T. Amory, Mem. (1769), II. 156. On which are fastened curve pieces of wood.
c. 1865. Brougham, Introd. Disc., in Circ. Sc., I. p. xi. The Earth moves round the Sun in the same curve line.
B. sb. (Short for curve-line, etc.: cf. F. courbe = ligne courbe.)
1. Geom. A curved line: a locus which may be conceived to be traced by a moving point, the direction of whose motion continuously changes or deviates from a straight line. (In Higher Geometry, extended to include the straight line.)
Algebraic curve: a curve expressed by an equation containing only algebraic functions, i.e., such as involve only addition, multiplication, involution, and their converses; of which kind are the various conic sections: opposed to transcendental (or mechanical) curve, one which can be expressed only by an equation involving higher functions, as the catenary, cycloid, etc. Curve of probability: a transcendental curve representing the probabilities of recurrences of an event. Curve of pursuit: the curve traced by a point moving with constant velocity, whose motion is directed at each instant towards another point which also moves with constant velocity (usually in a straight line). Curve of sines: a curve in which the abscissa is proportional to some quantity and the ordinate to the sine of that quantity; so also curve of cosines, tangents, etc. See also ANACLASTIC, CATENARY, CAUSTIC, CUBIC, EXPONENTIAL, etc. etc.
1696. Whiston, Th. Earth, I. 22. All Bodies … which revolve in Curves … are attracted … continually towards that Point or Center.
1706. H. Ditton, Fluxions, 221. That Curve to which this Property agrees, must be the Curve of swiftest Descent.
1751. Chambers, Cycl., Radial curves, is a denomination given by some authors to curves of the spiral kind, whose ordinates … all terminate in the centre of the including circle, and appear like so many radii … whence the name.
1871. Tait & Steele, Dynamics of a Particle (ed. 3), i. § 32. Illustrations … are to be found in what are called Curves of Pursuit. These questions arose from the consideration of the path taken by a dog who in following his master always directs his course towards him.
1875. Jevons, Money (1878), 138. The curve … shows the course of variation of the standard of value.
1882. Minchin, Unipl. Kinemat., 38. What curve do the chalk marks make in the rolling body? Evidently … a circle…. What curve do the chalk marks make on the fixed plane? Evidently a right line.
† b. A curved surface. Obs.
1728. trans. Newton’s Opt. Lect., 173. The Refraction of a Ray by a Curve is the same, as by a Plane touching the Curve in the Point of Refraction.
2. A curved form, outline, etc.; a curved thing or portion of a thing.
1728. Pope, Dunc., II. 172. It rose, and labour’d to a curve at most.
1750. Franklin, Experiments, Wks. 1887, II. 203. Take a wire bent in the form of a C, with a stick of wax fixed to the outside of the curve to hold it by.
1783. P. Pott, Chirurg. Wks., III. 407. A smart blow, or a violent strain had immediately preceded the appearance of the curve [of the spine].
1856. Kane, Arct. Expl., II. xi. 112. Etah is on the northeastern curve of Hartstene Bay.
3. (See quot.)
1874. Knight, Dict. Mech., Curve, a draftsman’s instrument having one or a variety of curves of various characters…. Some are constructed for specific purposes, such as shipwright’s curses, radii-curves, etc.
4. Base-ball. ‘The course of a ball so pitched that it does not pass in a straight line from the pitcher to the catcher, but makes a deflection in the air other than the ordinary one caused by the force of gravity’ (Cent. Dict.).
C. Comb., as † curve-lined a., composed of curved lines, curvilinear; curve-ruler (see quot.); curve-veined a. (of leaves), having veins diverging from the midrib and converging towards the margin.
1677. Plot, Oxfordsh., 288. Innumerable sorts of *Curve-lined figures.
c. 1865. Brougham, Introd. Disc., in Circ. Sc., I. p. vi. There are curve-lined figures as well as straight.
1879. T. Baker, Land & Eng. Surv., 159. Railway *Curve-rulers are a series of arcs of circles of various radii … used for projecting railway curves on parliamentary maps.
1866. Treas. Bot., 364. Curvinerved, *Curve-veined, the same as Convergentinervose.
1870. Bentley, Bot., 147.
