bitch hook
n.— «The sleigh wanted to hurtle down the hill, running over the horses. The solution to this was to get off, and apply what was called a “block chain” around the runner, with a hook known as a “bitch hook,” because it hung on so tightly that it wouldn’t let go. Now the horses could pull the sleigh down, rather than have to brake it all the way.» —“Times Past” by Paul Tapley Fall at Muskoka Resorts (North Muskoka, Ontario, Can.) Nov. 7, 2005. (source: Double-Tongued Dictionary)