**The Collaborative International Dictionary of English v.0.48:**

Plane \Plane\, a. [L. planus: cf. F. plan. See Plan, a.]
Without elevations or depressions; even; level; flat; lying
in, or constituting, a plane; as, a plane surface.
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Note: In science, this word (instead of plain) is almost
exclusively used to designate a flat or level surface.
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Plane angle, the angle included between two straight lines
in a plane.
Plane chart, Plane curve. See under Chart and Curve.
Plane figure, a figure all points of which lie in the same
plane. If bounded by straight lines it is a rectilinear
plane figure, if by curved lines it is a curvilinear plane
figure.
Plane geometry, that part of geometry which treats of the
relations and properties of plane figures.
Plane problem, a problem which can be solved geometrically
by the aid of the right line and circle only.
Plane sailing (Naut.), the method of computing a ship's
place and course on the supposition that the earth's
surface is a plane.
Plane scale (Naut.), a scale for the use of navigators, on
which are graduated chords, sines, tangents, secants,
rhumbs, geographical miles, etc.
Plane surveying, surveying in which the curvature of the
earth is disregarded; ordinary field and topographical
surveying of tracts of moderate extent.
Plane table, an instrument used for plotting the lines of a
survey on paper in the field.
Plane trigonometry, the branch of trigonometry in which its
principles are applied to plane triangles.
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**The Collaborative International Dictionary of English v.0.48:**

Curve \Curve\, n. [See Curve, a., Cirb.]
1. A bending without angles; that which is bent; a flexure;
as, a curve in a railway or canal.
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2. (Geom.) A line described according to some low, and having
no finite portion of it a straight line.
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Axis of a curve. See under Axis.
Curve of quickest descent. See Brachystochrone.
Curve tracing (Math.), the process of determining the
shape, location, singular points, and other peculiarities
of a curve from its equation.
Plane curve (Geom.), a curve such that when a plane passes
through three points of the curve, it passes through all
the other points of the curve. Any other curve is called a
curve of double curvature, or a twisted curve.
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