Si see Your browser does not support the audio element. [ French , B ] Definition The raised fifth tone in a scale or the ninth tone of a chromatic scale. In the "fixed Do" system, Si is always G sharp. The French, Italian and Spanish term for the pitch G sharp. See more about syllables of solmization in the Appendix. See more about pitches in the Appendix. See more about pitch frequencies in the Appendix. See more about modern scale construction in the Appendix. Share Share on Facebook (opens in a new tab) Share on X (opens in a new tab) Last Updated: 2013-02-14 19:31:02