A harpsichord was a musical instrument originating from 16th century Earth. It was a keyboard instrument similar to a piano, but created musical notes by plucking strings rather than striking them.
Wanda Landowska was famed for reviving interest in harpsichord music in the early 20th century, and for recording the works of Johann Sebastian Bach on this instrument. Elizabeth Lense enjoyed Landowska's harpsichord music, as did her child. (CoE eBook: Ghost)
By 2281, Sethan had built three harpsichords, including an eight foot one based on a 16th century model. (TOS novel: Dwellers in the Crucible)