Somewhat gray; grayish.n. ; pl. grizzlies (-liz). 1. The grizzly bear, Ursus horribilis. See I.n. In mining: An arrangement in the sluices used in washing auriferous gravel for receiving and throwing out the large stones carried down by the current.n. In Australia, a coarse grating of timber for separating large pieces of quartz from the decomposed rock with which they are associated, in some of the forms of granitic dikes containing auriferous quartz peculiar to that region.n. A machine used for breaking coal or other material to a moderately small size.