in·ci·dence /ˈɪn(t)sədən(t)s, ˌdɛn(t)s/
in·ci·dence /ˈɪn(t)sədən(t)s, səˌdɛn(t)s/ 名詞
1. A falling on or upon; an incident; an event; an occurrence. [Obs.]
2. 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.
n 1: the relative frequency of occurrence of something [syn: relative
2: the striking of a light beam on a surface; "he measured the
angle of incidence of the reflected light"