Brockville, a town and port of entry of Ontario, Canada, and capital of Leeds county, named after General Sir Isaac Brock, situated 119 m. S.W. of Montreal, on the left bank of the St Lawrence, and on the Grand Trunk, and Brockville & Westport railways. A branch line connects it with the Canadian Pacific. It has steamer communication with the St Lawrence and Lake Ontario ports, and is a summer resort. The principal manufactures are hardware, furnaces, agricultural implements, carriages and chemicals. It is the centre of one of the chief dairy districts of Canada, and ships large quantities of cheese and butter. Pop. (1881) 7609; (1901) 8940.