a·ton·al / āˈtōnl/ • adj. Mus. not written in any key or mode.DERIVATIVES: a·ton·al·ism / -ˌizəm/ n.a·ton·al·ist / -ist/ n.a·to·nal·i·ty / ˌātōˈnalitē;/ n.

atonal. Not in any key, hence atonality. Schoenberg preferred the term pantonal, denoting synthesis of all keys. Atonality is usually applied where there is no tonal centre and the notes of the chromatic scale are used impartially: the 12 notes of the octave function independently, unrelated to a key centre. Atonality is foreshadowed in the mus. of Debussy and Scriabin, even Liszt, but can perhaps be dated from the finale of Schoenberg's 2nd str. qt. (1908). From atonality there developed the twelve-note system. With atonality, consonances and dissonances of trad. harmony no longer apply.