Etymology : Middle English, from Latin triangulum, from neuter of triangulus triangular, from tri- + angulus angle
Pronunciation : 'trI-"a[ng]-g&l
Function : noun
Date : 14th century
1. shape having three sides and three corners, three-sided polygon; group of three. triangle\tri"an`gle\ , n. [l. triangulum, fr. triangulus triangular; tri- (see:
tri-) + angulus angle: cf. f. triangle. see:
angle a corner.].
2. (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.
3. (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.
4. a draughtsman's square in the form of a right-angled triangle.
5. (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.
6. (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?l.), a small american spider (hyptiotes americanus) of the family ciniflonid?, 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.triangle n.
7. a three-sided polygon [syn: trigon, trilateral].
8. any of various triangular drafting instruments used to draw straight lines at specified angles.
9. a percussion instrument consisting of a metal bar bent in the shape of an open triangle.
10. A figure bounded by three lines, and containing three angles.
11. 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.
12. A draughtsman's square in the form of a right- angled triangle.
13. 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.
14. A small constellation situated between Aries and Andromeda.
15. A small constellation near the South Pole, containing three bright stars. a percussion instrument consisting of a metal bar bent in the shape of an open triangle any of various triangular drafting instruments used to draw straight lines at specified angles a three-sided polygon something approximating the shape of a triangle; "the coastline of Chile and Argentina and Brazil forms two legs of a triangle".
16. 1. A triangle is an object, arrangement, or flat shape with three straight sides and three angles. Its outline roughly forms an equilateral triangle. triangles of fried bread.
17. The triangle is a musical instrument that consists of a piece of metal shaped like a triangle. You play it by hitting it with a short metal bar.
18. If you describe a group of three people as a triangle, you mean that they are all connected with each other in a particular situation, but often have different interests. She plays a French woman in a love triangle with Jonathan Pryce and Christopher Walken. see also:
eternal triangle. Geometric figure with three sides and three angles. Each two sides meet at a point called a vertex, and the three angles sum to 180°. A triangle with one 90° (right) angle is a right triangle. A triangle with all sides (and thus all angles) equal is equilateral, one with two sides equal is isosceles, and one with no two sides equal is scalene. Triangles are particularly useful in surveying, astronomy, and navigation. Two observation points (sight lines) form a triangle with a reference object serving as one vertex and the observation points as the other two. Knowing the angles of the sight lines and the distance between the observation points allows the calculation of the lengths of the other sides using the methods of trigonometry.