Webster’s Revised Unabridged Dictionary · 1913
Piano
Pi·a′no (pē·ä′nō), a. & adv. [It., even, smooth, soft, fr. L. planus even, level.] (Mus.) Soft; — a direction to the performer to execute a certain passage softly, and with diminished volume of tone. (Abbrev. p.)
Pi·an′o, Pi·an′o·for′te, n. [It. piano soft (fr. L. planus even, smooth; see Plain, a.) + It. forte strong, fr. L. fortis (see Fort).] (Mus.) A well-known musical instrument somewhat resembling the harpsichord, and consisting of a series of wires of graduated length, thickness, and tension, struck by hammers moved by keys.
Dumb piano. See Digitorium. — Grand piano. See under Grand. — Square piano, one with a horizontal frame and an oblong case. — Upright piano, one with an upright frame and vertical wires.