What does Boxing Day have to do with boxing?
c.1300, "deficiency, shortage," from Old Norse vant, neuter of vanr "wanting, deficient;" related to Old English wanian "to diminish" (see wane). Phrase for want of is recorded from c.1400. Meaning "state of destitution" is recorded from mid-14c. Newspaper want ad is recorded from 1897. Middle English had wantsum (c.1200) "in want, deprived of," literally "want-some."