angle of incidence

English Thesaurus

1. the angle that a line makes with a line perpendicular to the surface at the point of incidence (noun.shape)

hypernym	:	angle,
definition	:	the space between two lines or planes that intersect; the inclination of one line to another; measured in degrees or radians (noun.shape)

hyponym	:	angle of attack,
definition	:	the acute angle between the direction of the undisturbed relative wind and the chord of an airfoil (noun.shape)

hyponym	:	critical angle,
definition	:	the smallest angle of incidence for which light is totally reflected (noun.shape)