gamut

[15] Gamut began life as a medieval musical term. The 11th-century French-born musical theorist Guido d’Arezzo devised the ‘hexachord’, a six-note scale used for sightreading music (and forerunner of the modern tonic sol-fa). The notes were mnemonically named ut, re, mi, fa, sol, la (after, according to legend, syllables in a Latin hymn to St John: ‘Ut queant laxis resonāre fibris Mira gestorum famuli tuorum, Solve polluti labii reatum’ – ‘Absolve the crime of the polluted lip in order that the slaves may be able with relaxed chords to praise with sound your marvellous deeds’). The note below the lowest note (ut) became known as gamma-ut (gamma, the name of the Greek equivalent of g, having been used in medieval notation for the note bottom G). And in due course gamma-ut, or by contraction in English gamut, came to be applied to the whole scale, and hence figuratively to any ‘complete range’ (an early 17th-century development).

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   The word for an entire range or scale derives from Medieval Latin, in which it represented gamma ut, from gamma (the Greek letter), the lowest note of the hexachord as established in the 11th century by Guido d'Arezzo, and ut, the first note (now do) of the scale ut, re, mi, fa, sol, la, si. These derive from a Latin hymn to St. John: 'Ut queant laxis resonare fibris, Mira gestorum famuli tuorum, Solve polluti labii reatum, Sancte Iohannes.'