What does Boxing Day have to do with boxing?
"to eat too much," 1590s, from over- + eat (v.). Related: Overate; overeating. Old English had oferæt (n.) "gluttony; oferæte (adj.) "gluttonous."
overeat o·ver·eat (ō'vər-ēt')v. o·ver·ate (-āt'), o·ver·eat·en (-ēt'n), o·ver·eat·ing, o·ver·eats To eat to excess, especially habitually.