( n. )
A scale series of four sounds, of which the extremes, or first and last, constituted a fourth. These extremes were immutable; the two middle sounds were changeable.
( n. )
A scale series of four sounds, of which the extremes, or first and last, constituted a fourth. These extremes were immutable; the two middle sounds were changeable.
Webster's Revised Unabridged English Dictionary. Пересмотренный полный словарь английского языка Webster. 2012