- a movement in experimental, nonrepresentational painting originating in the U.S. in the 1940s, with sources in earlier movements, and embracing many individual styles marked in common by freedom of technique, a preference for dramatically large canvases, and a desire to give spontaneous expression to the unconscious.
- a school of painting in New York in the 1940s that combined the spontaneity of expressionism with abstract forms in unpremeditated, apparently random, compositions
