1. (sometimes caps.) Also called tachism. a style of American abstract expressionist painting typified esp. in the works of Jackson Pollack and Willem de Kooning in the 1940s, in which the furiously energetic and free application of the paint is seen as being expressive of the psychological and emotional state of the artist at the moment of creation.
2. See abstract expressionism.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.