music

mid-13c., musike, from Old French musique (12c.) and directly from Latin musica "the art of music," also including poetry (also source of Spanish musica, Italian musica, Old High German mosica, German Musik, Dutch muziek, Danish musik), from Greek mousike (techne) "(art) of the Muses," from fem. of mousikos "pertaining to the Muses," from Mousa "Muse" (see muse (n.)). Modern spelling from 1630s. In classical Greece, any art in which the Muses presided, but especially music and lyric poetry.

The use of letters to denote music notes is probably at least as old as ancient Greece, as their numbering system was ill-suited to the job. Natural scales begin at C (not A) because in ancient times the minor mode was more often used than the major one, and the natural minor scale begins at A.