Limn is a verb that means "to represent" or "portray." It is most often used to describe the act of drawing or painting a portrait, but it can also refer to describing or outlining a scene or event.
The verb limn evolved from the Latin lumināre, "to illuminate." The word referred originally to coloring (illuminating) manuscripts. The sense of "portray" or "depict" did not come into use until the late 16th century, but that meaning is close to the original, since someone who paints a portrait usually illuminates something about the subject's character. The word is less often used of written description, as in "Her reviews tended to limn the worst aspects of the performance, ignoring the best."