What does Boxing Day have to do with boxing?
foot deformity, 1800, from Latin varus, literally "knock-kneed."
varus var·us (vâr'əs, vār'-)
Characterized by an abnormal inward turning of a bone, especially of the hip, knee, or foot; occasionally used to indicate an outward turning. n.
A bone of the leg or foot characterized by such an abnormality.