Definition of harmonist
plural -s
1 a
:a member of a school of theorists in ancient Greece who intensively investigated the mathematical basis for musical pitch relations
b
archaic
:a person who composes or performs music
c
:a composer who emphasizes harmony above other musical elements
d
:a musician skilled in performing or improvising harmony
e
:a collection of songs or hymns
- a religious songbook titled The Devotional Harmonist
2
:one who shows the agreement or harmony of corresponding passages of different literary works (as the Gospels)
- editorial harmonists of the Pentateuch
- —Interpreter's Bible
3
:harmonizer
4
usually capitalized
[Harmony, community in Pennsylvania + English -ist]
: harmonite 
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