Ge*om"e*tral (?), a. [Cf. F. gÈomÈtral.] Pertaining to geometry. [Obs.]

{ Ge`o*met"ric (?), Ge`o*met"ric*al (?), } a. [L. geometricus; Gr. &?;:

cf. F. gÈomÈtrique.] Pertaining to, or according to the rules or

principles of, geometry; determined by geometry; as, a geometrical

solution of a problem.

Geometric is often used, as opposed to algebraic, to include processes

or solutions in which the propositions or principles of geometry are

made use of rather than those of algebra.

Geometrical is often used in a limited or strictly technical sense, as

opposed to mechanical; thus, a construction or solution is geometrical

which can be made by ruler and compasses, i. e., by means of right

lines and circles. Every construction or solution which requires any

other curve, or such motion of a line or circle as would generate any

other curve, is not geometrical, but mechanical. By another

distinction, a geometrical solution is one obtained by the rules of

geometry, or processes of analysis, and hence is exact; while a

mechanical solution is one obtained by trial, by actual measurements,

with instruments, etc., and is only approximate and empirical.

Geometrical curve. Same as Algebraic curve; -- so called because their

different points may be constructed by the operations of elementary

geometry. -- Geometric lathe, an instrument for engraving bank notes,

etc., with complicated patterns of interlacing lines; -- called also

cycloidal engine. -- Geometrical pace, a measure of five feet. --

Geometric pen, an instrument for drawing geometric curves, in which the

movements of a pen or pencil attached to a revolving arm of adjustable

length may be indefinitely varied by changing the toothed wheels which

give motion to the arm. -- Geometrical plane (Persp.), the same as

Ground plane . -- Geometrical progression, proportion, ratio. See under

Progression, Proportion and Ratio. -- Geometrical radius, in gearing,

the radius of the pitch circle of a cogwheel. Knight. -- Geometric

spider (Zoˆl.), one of many species of spiders, which spin a

geometrical web. They mostly belong to Epeira and allied genera, as the

garden spider. See Garden spider. -- Geometric square, a portable

instrument in the form of a square frame for ascertaining distances and

heights by measuring angles. -- Geometrical staircase, one in which the

stairs are supported by the wall at one end only. -- Geometrical

tracery, in architecture and decoration, tracery arranged in

geometrical figures.

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Ge`o*met"ric*al*ly (?), adv. According to the rules or laws of

geometry.

Ge*om`e*tri"cian (?), n. One skilled in geometry; a geometer; a

mathematician.

Ge*om"e*trid (?), a. (Zoˆl.) Pertaining or belonging to the GeometridÊ.

Ge*om"e*trid, n. (Zoˆl.) One of numerous genera and species of moths,

of the family GeometridÊ; -- so called because their larvÊ (called

loopers, measuring worms, spanworms, and inchworms) creep in a looping

manner, as if measuring. Many of the species are injurious to

agriculture, as the cankerworms.

Ge*om"e*trize (?), v. i. [imp. & p. p. Geometrized (?); p. pr. & vb. n.

Geometrizing (?).] To investigate or apprehend geometrical quantities

or laws; to make geometrical constructions; to proceed in accordance

with the principles of geometry.

Nature geometrizeth, and observeth order in all things.

Sir T. Browne.

Ge*om"e*try (?), n.; pl. Geometries (#) [F. gÈomÈtrie, L. geometria,

fr. Gr. &?;, fr. &?; to measure land; ge`a, gh^, the earth + &?; to

measure. So called because one of its earliest and most important

applications was to the measurement of the earth's surface. See

Geometer.] 1. That branch of mathematics which investigates the

relations, properties, and measurement of solids, surfaces, lines, and

angles; the science which treats of the properties and relations of

magnitudes; the science of the relations of space.

The Gutenberg Webster's Unabridged Dictionary: Section F, G and H · 第 1366 / 2879 题