Source : Webster's Revised Unabridged Dictionary (1913)

Harmonist \Har"mo*nist\, Harmonite \Har"mo*nite\, n. (Eccl.
   Hist.)
   One of a religious sect, founded in W["u]rtemburg in the last
   century, composed of followers of George Rapp, a weaver. They
   had all their property in common. In 1803, a portion of this
   sect settled in Pennsylvania and called the village thus
   established, Harmony.

Harmonist \Har"mo*nist\, n. [Cf. F. harmoniste.]
   1. One who shows the agreement or harmony of corresponding
      passages of different authors, as of the four evangelists.

   2. (Mus.) One who understands the principles of harmony or is
      skillful in applying them in composition; a musical
      composer.