1660s, spinette, "small harpsichord," from older French espinette (1520s), from Italian spinetta, said by Scaliger to be a diminutive of spina "thorn, spine," from Latin spina "thorn" (see spine), so called because the strings were plucked with thorn-like quills. The other theory (favored by OED) dates to early 17c. and claims the word is from the name of the Venetian inventor, Giovanni Spinetti (fl. c.1503).
small form of the harpsichord, generally wing-shaped, with a single set of strings placed at an oblique angle to the keyboard. The wing-shaped spinet may have originated in Italy during the 16th century; later it became known in France and England.