IPA: /əˈtoʊnəlɪst/
KK: /əˈtoʊnəlɪst/
A person who creates music that does not follow traditional tonal rules, often using dissonance and unconventional structures.
The atonalist experimented with new sounds and forms in his latest composition.
Atonalist → It is formed from "a-" (meaning without) and "tonal" (from Latin "tonalis", meaning relating to tone) and the suffix "-ist" (meaning one who practices or is concerned with). The word refers to someone who is without tone or does not adhere to a tonal system in music.
Think of someone who is 'without' ('a-') 'tone' ('tonal') — that's why an atonalist is someone who does not follow traditional musical tones.