What is a key to tune a stringed instrument of music. The minstrel . . . wore round his neck a silver chain, by which hung the wrest, or key, with which he tuned his harp. Sir W. Scott called?

wrest — A key to tune a stringed instrument of music. The minstrel . . . wore round his neck a silver chain, by which hung the wrest, or key, with which he tuned his harp. Sir W. Scott. (Webster's 1913.)

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