A nihilistic art movement (especially in painting) that flourished in Europe early in the 20th century; based on irrationality and negation of the accepted laws of beauty WordNet 3.0 & Open English WordNet

Dada or Dadaism was an art movement of the European avant-garde in the early 20th century, with early centres in Zürich, Switzerland, at the Cabaret Voltaire. Wikipedia

A cultural movement that started in Switzerland and peaked from 1916 to 1922, which rejects reason and logic, prizing nonsense, irrationality and intuition. OmegaWiki

A cultural movement that began in Zürich, Switzerland during and as a reaction to World War I and peaked from 1916 to 1920, which primarily involved visual arts, literature (mainly poetry), theatre, and graphic design, and was characterized by deliberate irrationality, disillusionment, cynicism, nihilism, randomness, and rejection of the prevailing standards in art. Wiktionary

The cultural movement of Dada. Wiktionary