thurl

noun[in the plural]1

1. •
   Either of the rear hip joints where the hip connects to the upper leg in certain animals, particularly cattle; often used as a reference point for measurement.

   • Deficiencies which are common to the hind quarters of the cow, include shortness and narrowness of rump, a drooping rump, narrowness between the thurls and pin bones and thickly fleshed thighs. — 1918