What is the origin of tocsin?

Tocsin, “a signal, especially an alarm sounded on a bell,” comes via Old French toquesin, touquesaint, tocsaint from Provençal tocasenh. Tocasenh is a compound made up of the verb tocar “to strike” (French toucher, English touch), from Vulgar Latin toccāre “to touch” and senh “a bell, note of a bell,” from Medieval Latin signum “a bell,” from Latin signum “a mark or sign; a signal.” Tocsin entered English in the second half of the 16th century.