A description generally applied to aspects of modern American painting in the late 1940s and early 1950s which were concerned both with the various forms of abstraction and with psychic self-expression. Abstract Expressionism was more of an attitude than a style, drew on many historical sources from Van Gogh to Matisse and Kandinsky, and embraced a wide variety of paintings ranging from the drip paintings of Jackson Pollock to the intensely coloured floating shapes of Mark Rothko.
Text source: The Oxford Concise Dictionary of Art Terms (2nd Edition) by Michael Clarke