'Dioptrical' definitions:
Definition of 'Dioptrical'
From: GCIDE
- Dioptric \Di*op"tric\, Dioptrical \Di*op"tric*al\, a. [Gr. ? belonging to the use of the ?; ? = dia` through + the root of ? I shall see: cf. F. dioptrique.] Of or pertaining to dioptrics; assisting vision by means of the refraction of light; refractive; as, the dioptric system; a dioptric glass or telescope. "Dioptrical principles." --Nichol. [1913 Webster]
- Dioptric curve (Geom.), a Cartesian oval. See under Cartesian. [1913 Webster]