MEMPHREMAGOG, mĕm-frĕ-mā'gŏg, a lake in the southern part of the province of Quebec, Canada, extending into Orleans County, in Vermont. It is about 30 miles long, north and south, and from three-quarters of a mile to three miles wide. It is irregular in shape, and along its shores are several striking indentations, in some places low and in some other parts high and rocky. The land on the west shore is mountainous, the altitude of the highest points being about 2,800 feet. The outlet is the Magog River, which flows into the Saint Francis River. Along the shore are a number of villages, and in summer a steamer plies daily on the lake, connecting the chief towns and villages.