an optical instrument, often attached to the eyepiece of a microscope, by which the image of an external object is projected on a sheet of paper or the like for tracing.
Origin: 1660–70; < NL: bright chamber; see camera, lucid
Main Entry: cam·era lu·ci·da Pronunciation: "kam-(&-)r&-'lü-s&d-& Function: noun : an instrument that by means of aprism or mirrors and often a microscope causes a virtual image of an object to appear as if projected upon a plane surface so that an outline may be traced
[loo-si-duh] 
sɪ