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meantone system

American  
[meen-tohn] / ˈminˌtoʊn /

noun

Music.
  1. a system for tuning keyboard instruments, used before the development of tuning by equal temperament and considered practical only for tonalities of not more than two sharps or flats.


Etymology

Origin of meantone system

First recorded in 1790–1800; mean 3 + tone