Wiktionary
n. (context music English) A genre of experimental electronic music that combines elements of techno and dance music with complex rhythmic structures and atypical melodic patterns.
Wikipedia
Intelligent dance music (IDM) is a genre of electronic music that emerged in the early 1990s. Its creation was influenced by developments in underground dance music such as Detroit techno and various breakbeat styles that were emerging in the UK at that time. Stylistically, IDM tended to rely upon individualistic experimentation rather than adhering to musical characteristics associated with specific genres of dance music. The range of post-techno styles to emerge in the early 1990s were described variously as "art techno", "ambient techno", "intelligent techno", and " electronica". In the United States, the latter is often used as a catchall term to describe not only downtempo or downbeat/non-dance electronic music but also electronic dance music (EDM).
The term "IDM" is said to have originated in the United States in 1993 with the formation of the "IDM list", an electronic mailing list originally chartered for the discussion of music by a number of prominent English artists, especially those appearing on a 1992 Warp Records compilation called Artificial Intelligence.
Usage of the term "intelligent dance music" has been criticised by electronic musicians such as Aphex Twin as derogatory towards other styles and is seen by artists such as Mike Paradinas as being particular to the U.S. In 2014, music critic Sasha Frere-Jones observed that the term "is widely reviled but still commonly used". He regards UK acts Aphex Twin and Autechre as central to the evolution of the genre.