Camera Obscura

Part of speech: noun (n.)

1. An apparatus in which the images of extermal objects, formed by a convex lens or a concave mirror, are thrown on a paper or other white surface placed in the focus of the lens or mirror within a darkened chamber, or box, so that the oulines may be traced.

2. An apparatus in which the image of an external object or objects is, by means of lenses. thrown upon a sensitized plate or surface placed at the back or an extensible darkened box or chamber variously modifled; -- commonly called simply the camera.