Dictionary Meaning and Definition on 'Triangle'
- a three-sided polygon [syn: trigon, trilateral]
- something approximating the shape of a triangle; "the coastline of Chile and Argentina and Brazil forms two legs of a triangle"
- any of various triangular drafting instruments used to draw straight lines at specified angles
- a percussion instrument consisting of a metal bar bent in the shape of an open triangle
- Triangle \Tri"an`gle\, n. [L. triangulum, fr. triangulus
triangular; tri- (see Tri-) + angulus angle: cf. F.
triangle. See Angle a corner.]
- (Geom.) A figure bounded by three lines, and containing three angles. Note: A triangle is either plane, spherical, or curvilinear, according as its sides are straight lines, or arcs of great circles of a sphere, or any curved lines whatever. A plane triangle is designated as scalene, isosceles, or equilateral, according as it has no two sides equal, two sides equal, or all sides equal; and also as right-angled, or oblique-angled, according as it has one right angle, or none; and oblique-angled triangle is either acute-angled, or obtuse-angled, according as all the angles are acute, or one of them obtuse. The terms scalene, isosceles, equilateral, right-angled, acute-angled, and obtuse-angled, are applied to spherical triangles in the same sense as to plane triangles.
- (Mus.) An instrument of percussion, usually made of a rod of steel, bent into the form of a triangle, open at one angle, and sounded by being struck with a small metallic rod.
- A draughtsman's square in the form of a right-angled triangle.
- (Mus.) A kind of frame formed of three poles stuck in the ground and united at the top, to which soldiers were bound when undergoing corporal punishment, -- now disused.
- (Astron.) (a) A small constellation situated between Aries and Andromeda. (b) A small constellation near the South Pole, containing three bright stars. Triangle spider (Zo["o]l.), a small American spider (Hyptiotes Americanus) of the family Ciniflonid[ae], living among the dead branches of evergreen trees. It constructs a triangular web, or net, usually composed of four radii crossed by a double elastic fiber. The spider holds the thread at the apex of the web and stretches it tight, but lets go and springs the net when an insect comes in contact with it.
Wikipedia Meaning and Definition on 'Triangle'
A triangle is one of the basic shapes of geometry: a polygon with three corners or vertices and three sides or edges which are line segments. A triangle with vertices A, B, and C is denoted ABC.
In Euclidean geometry any three non-collinear points determine a unique triangle and a unique plane (i.e. a two-dimensional Euclidean space).
Triangles can be classified according to the relative lengths of their sides:
.[See more about Triangle at Dictionary 3.0 Encyclopedia]
Words and phrases related to 'Triangle'