What does Boxing Day have to do with boxing?
mid-14c., "enduring without complaint," from Old French pacient and directly from Latin patientem (see patience). Related: Patiently.
"suffering or sick person under medical treatment," late 14c., from Old French pacient (n.), from the adjective, from Latin patientem (see patience).
patient pa·tient (pā'shənt)n. One who receives medical attention, care, or treatment.