in musical composition, "not considering scale or tone," 1911, from a- (3) "not, without" + tonal.
Entries linking to atonal
a- 3
prefix meaning "not, without," from Greek a-, an- "not" (the "alpha privative"), from PIE root *ne- "not" (source also of English un-).
In words from Greek, such as abysmal, adamant, amethyst; also partly nativized as a prefix of negation (asexual, amoral, agnostic). The ancient alpha privatum, denoting want or absence.
Greek also had an alpha copulativum, a- or ha-, expressing union or likeness, which is the a- expressing "together" in acolyte, acoustic, Adelphi, etc. It is from PIE root *sem- (1) "one; as one, together with."
tonal adj.
1776; from tone (n.) in the musical sense + -al (1), or from Medieval Latin tonalis.
atonality n.
"state or quality of being atonal," 1919, in reference to the works of Erik Satie; see atonal + -ity.