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

But plaine angles making a solid angle, are lesser than foure right angles, by the 8 e xxij.

From The Way To Geometry by Bedwell, William

The second solid is composed of the same triangles, which unite as eight equilateral triangles, and make one solid angle out of four plane angles—six of these angles form a regular octahedron.

From Timaeus by Jowett, Benjamin

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

From The Way To Geometry by Bedwell, William

The normal section of the cone at that point is equal to dS cosθ, and the solid angle dω is equal to dS cosθ / x�.

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

There is no telling what the web and rivets would have borne had not the solid angle irons given way at the first bend.

From Scientific American Supplement, No. 648, June 2, 1888. by Various