The grey wolf (S. "draugwath"; pl. "draugwaith"; Q. "mistanarmo"; pl. "mistanarmor"; aka "sindanarmo") sometimes known as "Timber-Wolf", was a powerful, muscular dog with a thick coat of hair and a bushy tail. They ranged all over Middle-earth. Varying in color from nearly black in warmer locales to almost white in the North, they were exceptionally adaptable.

Grey wolves were exceptionally social animals who lived in family groups or packs that roamed and hunted together. These packs cooperated to run down their favorite prey: generally deer and sheep in the warmer climes and elk or reindeer in cooler regions. While typically interested only in larger herd animals, they also fed on rodents, fish, and crustaceans and, in rare cases (e.g., during hard winters or famines), they might attack lone travellers, trappers, or hunters.

The wolfpack's hierarchy was organized and regulated in accord with the wolves' ritualized postures, gestures, and combat. Grey wolves, however, did not fight over mates except in extraordinary circumstances. Pairs normally remained together for life.