angle of incidence is a noun meaning "the angle that a line makes with a line perpendicular to the surface at the point of incidence". It carries one recorded sense.
the angle that a line makes with a line perpendicular to the surface at the point of incidence
Definitions, synonyms and semantic relations for angle of incidence come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.