psaltery, stringed musical instrument. It has a flat soundboard over which a variable number of strings are stretched. Its origin was in the Middle East, and it is referred to in the Bible. It appeared in Europe in the 12th cent. and flourished until the late Middle Ages. The term psaltery is sometimes used as a generic term for all plucked zithers having flat bodies. The instrument is similar to a hammered dulcimer but is plucked instead of hammered.