noun
definition
A side exactly corresponding, or equal, to others.
definition
A figure having all its sides equal.
adjective
definition
(of a polygon) Having all the sides equal.
definition
(of a polyhedron) Having all the faces equal.
definition
Having the two sides equal, as a surface divisible by a longitudinal median line into two halves of the same form.
definition
Having all the convolutions of the shell in one plane, chiefly of foraminifers.
Examples of equilateral in a Sentence
In a similar manner, four covertical equilateral triangles stand on a square base.
If the faces be all equal equilateral triangles the solid is termed the "regular" tetrahedron.
The base of the equilateral triangle is the top of the wedge.
Five equilateral triangles covertically placed would stand on a pentagonal base, and it was found that, by forming several sets of such pyramids, a solid could be obtained which had zo triangular faces, which met in pairs to form 30 edges, and in fives to form 12 vertices.
The regular octahedron has for its faces equilateral triangles; it is the reciprocal of the cube.
Nicaragua forms an irregular equilateral triangle with its base stretching for 280 m.
The equilateral triangle is the basis of the tetrahedron, octahedron and icosahedron.'
Omega Centauri makes an almost equilateral triangle with these two stars on their western side.
While this design may have been traditional, the shape of the new 50p coin, an equilateral curve heptagon, was revolutionary.
In crystallography the icosahedron is a possible form, but it has not been observed; it is closely simulated by a combination of the octahedron and pentagonal dodecahedron, which has twenty triangular faces, but only eight are equilateral, the remaining twelve being isosceles (see Crystallography).
Ladenburg (Ber., 2, p. 140) devised his prism formula (IV), the six carbon atoms being placed at the six corners of a right equilateral triangular prism, with its plane projections (V, VI).
In shape roughly resembling an equilateral triangle, with base uppermost, Bosnia and Herzegovina cover an area of 19,696 sq.
Incidentally Pappus describes the thirteen other polyhedra bounded by equilateral and equiangular but not similar polygons, discovered by Archimedes, and finds, by a method recalling that of Archimedes, the surface and volume of a sphere.
Inside an equilateral triangle, for instance, of height h, - 2Ra/3y/h, (8) where a, 13, y are the perpendiculars on the sides of the triangle.
The isothermals are approximately equilateral hyperbolas (pv= constant), with the axes of p and v for asymptotes, for a gas or unsaturated vapour, but coincide with the isopiestics for a saturated vapour in presence of its liquid.
These problems were also attacked by the Arabian mathematicians; Tobit ben Korra (836-901) is credited with a solution, while Abul Gud solved it by means of a parabola and an equilateral hyperbola.
The theorem, then, seems to have been arrived at by induction, and may have been suggested by the contemplation of floors or walls covered with tiles of the form of equilateral triangles, or squares, or hexagons.
If three equilateral triangles be placed at a common vertex with their covertical sides coincident in pairs, it is seen that the base is an equal equilateral triangle; hence four equal equilateral triangles enclose a space.
A third reflecting plate is sometimes employed, the cross-section of the three forming an equilateral triangle.
The French army was thus disposed almost in an equilateral triangle with sides of about 570 m., with 95,000 men at the apex at Moscow opposed to 120,000, 30,000 about Brest opposite ioo,000, and 17,000 about Drissa confronted by 40,000, whilst in the centre of the base at Smolensk lay Victor's corps, about 30,000.
Octahedra having triangular faces other than equilateral occur as crystal forms. See Polyhedron and Crystallography.
In the case of a biaxal plate perpendicular to the bisector of the acute angle between the optic axes, the curves of constant retardation are approximately Cassini's ovals, and the lines of like polarization are equilateral hyperbolae passing through the points corresponding to the optic axes.