·adj Spreading widely, or generally prevailing; affecting great numbers, as an epidemic does; as, epidemic rage; an epidemic evil.
II. Epidemical ·adj Common to, or affecting at the same time, a large number in a community;
— applied to a disease which, spreading widely, attacks many persons at the same time; as, an epidemic disease; an epidemic catarrh, fever, ·etc. ·see Endemic.