curve (kerv)

and n. [In earlier use curb, A curve line is that which is neither a straight line nor composed of straight lines. Ogilvie. II. n. 1. A continuous bending; a flexure without angles; usually, as a concrete noun, a one-way geometrical locus which may be conceived as described by a point moving along a line round which as axis turns a plane, while the line rotates in the plane round the point. The curve is at the same time the envelop of the plane and of the line. Geometers understand a curve as something capable of being defined by an equation or equations, or otherwise described in general terms. It may thus have nodes, cusps, and other singularities, but must not be broken in a way which cannot be precisely defined without the use of special numbers. Curves are often employed in physics and statistics to represent graphically the changes in value of certain physical or statistical quantities: as, the energy curve of the solar spectrum; the isothermal line or curve; the curve of population. Nor pastoral rivulet that swerves To left and right thro' meadowy curves . Tennyson, In Memoriam, c. 2. Anything continuously bent.-3. A draftsman's instrument for forming curved figures. -4. In base - ball, the course of a ball so pitched that it does not pa 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: as, it was difficult to gage the curves of the pitcher. An in curve is one that deflects from the straight line toward the batter; an out curve, away from the batter. A drop deflects downward, and a rise or up curve upward.Adiabatic curve. See adiabatic. Algebraic curve, curve whose equations in linear coördinates contain only algebraic functions of the coördinates. - Anaclastic curves, an all agma tic curves. See the adjectives. Anticlinal and synclinal curves, in geol., terms applied to the elevations and depre ions of undulating surfaces of strata. See anticlinal and synclinal. Asymp to tical curves. See asymptotical . Axis of a curve. See axis1.- Bicursal curve, a curve which cannot be described by the continuous motion of one point, even if it pa es through infinity, but can be so described by two points. Bipartite curve, bitangential curve. See the adjectives. Cartes i an curve. Same as Cartes i an , n., 2.Catenary or catenarian curve. See catenary . Caustic curve. Same as caustic , n., 3. - Center of a curve. See center1 . Characteristic angle of a curve. See characteristic. Cla of a curve. See cla , 6.- Closed curve. See closel , v. Contact of two curves. See contact. Cubic curve, a curve of the third order, cutting every plane (or else every line in the plane) in three points. A cubic curve in a plane is one which is cut by every line in the plane in three points, real or imagi 1410 nary. Such curves are of three genera: nodal cubics, which have either a crunode or an acnode; cuspidal cubics, which have a cusp; and non-singular cubics, which are bicursal, though one branch may be imaginary.Curve coördinates. See coordinate. Curve of beau ty, a gentle curve of double or contrary flexure, in which it has been sought to trace the foundation of all beauty of curviserial Through the dewy meadow's breast, fringed with shade, but touched on one side with the sun-smile, ran the crystal river, curving in its brightne , like diverted hope. R. D. Black more , Lorna Doone, xxxiii.