sol-fa /ˌsɒl ˈfɑː $ ˌsoʊl-/ BrE AmE noun [uncountable]
[ Date: 1500-1600 ; Origin: sol + fa ]
the system in which the notes of the musical ↑ scale are represented by seven short words, ↑ do , ↑ re , ↑ mi , ↑ fa , ↑ so , ↑ la , ↑ ti , which are used especially in singing