Saint Hyacinthe (sānt hī´əsĬnth, Fr. săNtyäsăNt´), city (1991 pop. 38,292), S Que., Canada, on the Yamaska River, NE of Montreal. It is an industrial center, with textile mills and plants manufacturing rubber and paper products, furniture, shoes, and leather goods. The famous Casavant organ factory (est. c.1860) is there. There are institutions for religious education and schools of dairy husbandry, textile technology, and veterinary medicine.