sol.

(a loanword from Spanish)

Headword: 
sol.
Principal English Translation: 

a musical note

Attestations from sources in English: 

Syllables, such as this one, that represent musical notes and are sung in European song are attested in a seventeenth-century Guatemalan music manuscript.
Fernando Horcasitas y Alfred Lemmon, "El Tratado de Santa Eulalia: un manuscrito musical náhuatl," Tlalocan 12 (1997), 84–111.

Some of the many syllables attested: ut, sol, re, mi, fa, and la. The are sometimes combined, suc as rol-re, re-sol, sol-ut, ut-sol, re-ut, ut-re, sol-re, and so on. We also see B mol as B mor.
Fernando Horcasitas y Alfred Lemmon, "El Tratado de Santa Eulalia: un manuscrito musical náhuatl," Tlalocan 12 (1997), 84–111.