A vastly overworked word in the musical lexicon.
When encountered in tuning theory, it generally refers to the "whole tone", an interval size with the ratio 8:9, which is equivalent to 2.04 Semitones, ~203.9100017 cents, and approximately 1/6 of an octave.
It is also frequently used in a general sense to refer to an interval size of 2 semitones, whatever its exact cents value.
It is also frequently used in a very general sense to mean simply a sustained sound with a recognizable pitch, or to refer to an element in a set of pitches, as in a tuning system, scale, or chord; for example, 'a 7-tone scale'.
Any musical interval approximating 200 cents (¢).
In Just Intonation, the intervals [ratios] 10/9, 9/8, and 8/7 are all considered Whole Tones, in contrast to Half-Tones or Semitones such as 16/15 or 256/243.
Tone may also mean a musical sound.
It is equivalent to mode in late ecclesiastical music theory.
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