dulcimer n.

musical instrument with a trapezoidal body and metallic strings, late 15c., doucemer, from Old French doulce mer, variant of doulcemele, (compare obsolete Spanish dulcemele, Italian dolcemele), which is said to represent Latin *dulce melos, from dulce "sweet" (see dulcet) + melos "song" (from Greek melos "melody," which is of uncertain origin).