Webster's Revised Unabridged Dictionary · 1913

Harmonium

Harmonium (har*mō"ni*um) , noun

[New Latin See Harmony. ]

A musical instrument, resembling a small organ and especially designed for church music, in which the tones are produced by forcing air by means of a bellows so as to cause the vibration of free metallic reeds. It is now made with one or two keyboards, and has pedals and stops.