·noun A falling on or upon; an incident; an Event.
II. Incidence ·noun The direction in which a body, or a ray of light or heat, falls on any surface.
·add. ·- The angle between the chord of an aerocurve and the relative direction of the undisturbed a...
Webster's Dictionary of the English Language
See incidence, angle of. ...
The Sailor's Word-Book
That which the direction of a ray of light, &c., makes at the point where it strikes with a line dra...