incidence

incidence is defined in Webster's Unabridged Dictionary (1913) with 1 sense. The full text of each entry is reproduced verbatim below.

Definitions

  1. 1.(Physics) The direction in which a body, or a ray of light or heat, falls on any surface. In equal incidences there is a considerable inequality of refractions. Sir I. Newton. Angle of incidence, the angle which a ray of light, or the line of incidence of a body, falling on any surface, makes with a perpendicular to that surface; also formerly, the complement of this angle. -- Line of incidence, the line in the direction of which a surface is struck by a body, ray of light, and the like.

Source: Webster's Unabridged Dictionary, 1913 edition (public domain, via GCIDE / Project Gutenberg).

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