What does Boxing Day have to do with boxing?
late 14c., bocchen "to repair," later, "to spoil by unskillful work" (1520s); of unknown origin. Related: Botched; botching. As a noun from c.1600.
the name given in Deut. 28:27, 35 to one of the Egyptian plagues (Ex. 9:9). The word so translated is usually rendered "boil" (q.v.).