Ti
来自Big Physics
mid 19th century: alteration of si, adopted to avoid having two notes ( soh and si ) beginning with the same letter (see solmization).
wiktionary
Alteration of si, made so that every note of solfège would begin with a different letter.
From a Polynesian language, related to Hawaiian kī.
etymonline
ti
seventh note of the musical scale, 1842, earlier te (1839), replacing si to avoid confusion with so, sol (see gamut).
