(a) A gray fur, prob. the fur from the back of the Eurasian red squirrel Sciurus vulgaris in winter; red (ruskin) grei, the fur of the Eurasian red squirrel in winter; tristi (tresti) grei, ?error……
(a) Of a person: strong, powerful; violent, cruel; robust, healthy; of an army, a host, etc.: powerful, fierce, cruel; also, as noun: powerful or high-ranking people [quot. c1425]; stor and stark……