n. In art and lit., the doctrines and methods of the impressionists; the doctrine that natural objects should be painted or described as they first strike the eye in their immediate and momentary effects—that is, without selection, or artificial combination or elaboration.n. The name was first given to an advanced school of modern painting in France, based on the principle that effects of light in nature are momentary, and that the painter, if he wishes to be true to nature, should confine his attention and effort as closely as possible to the moment of their occurrence. In order to express the high key of natural light, a coterie of extreme impressionists, called pointillists, have used pure color laid on in points or dots. See the extract.