​ST HYACINTHE, a city and port of entry of Quebec, Canada, and capital of St Hyacinthe county, 32 m. E.N.E. of Montreal, on the left bank of the river Yamaska and on the Grand Trunk, Canadian Pacific, Intercolonial, and Quebec Southern railways. Pop. (1901) 9210. It is the seat of a Roman Catholic bishop, and contains a classical college, dairy school, two monasteries and several other educational and charitable institutions. It has manufactures of organs, leather, woollens and agricultural implements, and is an important distributing centre for the surrounding district.