solid angle

American  

noun

Geometry.

1. an angle formed by three or more planes intersecting in a common point or formed at the vertex of a cone.

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solid angle British  

noun

1. a geometric surface consisting of lines originating from a common point (the vertex) and passing through a closed curve or polygon: measured in steradians

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solid angle Scientific  

1. A three-dimensional angle, formed by three or more planes intersecting at a common point. Its magnitude is measured in steradians, a unitless measure. The corner of a room forms a solid angle, as does the apex of a cone; one can imagine an indefinite number of planes forming the smooth round surface of the cone all intersecting at the apex. Solid angles are commonly used in photometry.

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Etymology

Origin of solid angle

First recorded in 1695–1705

Example Sentences

See Examples For:

solid angle

Every solid angle is contained by plane angles, which are together less than four right angles—has no analogous theorem in the plane.

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6 "Geodesy" to "Geometry" by Various

Definition.—The solid angle subtended by any surface at a point is measured by the quotient of its apparent surface by the square of its distance from that point.

From Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 3 "Electrostatics" to "Engis" by Various

A similar difference exists between a solid angle and an n-edge or an n-flat.

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6 "Geodesy" to "Geometry" by Various

A solid angle is that which is made by more than two plane angles meeting in one point and not lying in the same plane, as the angle of a cube.

From The New Gresham Encyclopedia. Vol. 1 Part 2 Amiel to Atrauli by Various

This appeareth plainely out of the nature of a solid angle, by the kindes of plaine figures.

From The Way To Geometry by William Bedwell