1) A full-sized, preparatory drawing for a painting or tapestry. Video here. Web resource here. See also: pouncing.
Raphael. Cartoon for the School of Athens (det.). Ca. 1510. Charcoal and white lead on paper. Biblioteca Ambrosiana, Milan.
2) A typically simplified and/or exaggerated drawing intended for satire, caricature, or humor.
Cartoon by Mike Twohy. The New Yorker. 2001.