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zither vs. Autoharp

[zith-er, zith-] / ˈzɪθ ər, ˈzɪð- /

noun

  1. a musical instrument, consisting of a flat sounding box with numerous strings stretched over it, that is placed on a horizontal surface and played with a plectrum and the fingertips.

[aw-toh-hahrp] / ˈɔ toʊˌhɑrp /
Trademark.
  1. a zither having buttons that when depressed damp all strings except those to be sounded, the undamped strings being strummed to produce simple chords.