Emily Dickinson Lexicon

DI-OP'TRIC, or DI-OP'TRICAL, a. [Gr. διοπτρικος, from διοπτομαι, to see through; δια and οπτομαι, to see.]

1. Affording a medium for the sight; assisting the sight in the view of distant objects; as, a dioptric glass. – Boyle.
2. Pertaining to dioptrics, or the science of refracted light.