1. (n.) A solid whose bases or ends are any similar, equal, and parallel plane figures, and whose sides are parallelograms.

2. (n.) A transparent body, with usually three rectangular plane faces or sides, and two equal and parallel triangular ends or bases; -- used in experiments on refraction, dispersion, etc.

3. (n.) A form the planes of which are parallel to the vertical axis. See Form.

achromatic lens astigmatic lens burning glass camera coated lens concave lens concavo-convex lens condenser convex lens eyeglass eyepiece glass hand lens lens magnifier magnifying glass meniscus object glass objective objective prism ocular reader reading glass telephoto lens toric lens varifocal lens zoom lens