'antiharmonist' originates from Modern English, formed by the prefix 'anti-' (from Greek 'anti' meaning 'against') combined with 'harmonist', which derives from 'harmony' (Greek 'harmonia').

'harmonia' (Greek) passed into Latin as 'harmonia', then into Middle English as 'harmonie' and later became modern English 'harmony' and the agent noun 'harmonist'; 'antiharmonist' is a Modern English coinage created by adding the prefix 'anti-' to 'harmonist'.

Initially 'harmonia' meant 'joint, agreement' and evolved into the musical and social sense of 'harmony'; 'antiharmonist' developed to mean 'one opposed to harmony' and in music contexts has come to refer specifically to advocates of atonality or deliberate dissonance.