(n.) Of or pertaining to the science of vision; optical.
(n.) Pertaining to the art, or in accordance with the laws, of perspective.
(a.) A glass through which objects are viewed.
(a.) That which is seen through an opening; a view; a vista.
(a.) The effect of distance upon the appearance of objects, by means of which the eye recognized them as being at a more or less measurable distance. Hence, aerial perspective, the assumed greater vagueness or uncertainty of outline in distant objects.
(a.) The art and the science of so delineating objects that they shall seem to grow smaller as they recede from the eye; -- called also linear perspective.