A person who believes in or practices harmony; a musician who specializes in harmony; a member of a harmonistic religious community.
From harmony plus -ist (suffix indicating a practitioner, believer, or specialist). Also historically refers to members of Harmony, Indiana, a 19th-century religious communal settlement.
The -ist suffix is fascinating because it works for both professions (pianist, dentist) AND ideologies (socialist, harmonist)—so a harmonist could be someone studying musical harmony OR someone in a religious community dedicated to living in harmony, depending on context.
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