Wordnet 3.0
NOUN (1)
1.
the absence of a key;
alternative to the diatonic system;
[syn: atonality, atonalism]
WordNet (r) 3.0 (2006):
atonalism
n 1: the absence of a key; alternative to the diatonic system
[syn: atonality, atonalism] [ant: key, tonality]