What does Boxing Day have to do with boxing?
Old English ridan "sit or be carried on" (as on horseback), "move forward; rock; float, sail" (class I strong verb; past tense rad, past participle riden), from Proto-Germanic *ridanan (cf. Old Norse riða, Old Saxon ridan, Old Frisian rida "to ride," Middle Dutch riden, Dutch rijden, Old High Germn ritan, German reiten), from PIE *reidh- "to ride" (cf. Old Irish riadaim "I travel," Old Gaulish reda "chariot").
Meaning "heckle" is from 1912; that of "have sex with (a woman)" is from mid-13c.; that of "dominate cruelly" is from 1580s. To ride out "endure (a storm, etc.) without great damage" is from 1520s. To ride shotgun is 1963, from Old West stagecoach custom in the movies. To ride shank's mare "walk" is from 1846 (see shank (n.)).
1759, "journey on the back of a horse or in a vehicle," from ride (v.); slang meaning "a motor vehicle" is recorded from 1930; sense of "amusement park device" is from 1934. Meaning "act of sexual intercourse" is from 1937. To take (someone) for a ride "tease, mislead, cheat," is first attested 1925, American English, possibly from underworld sense of "take on a car trip with intent to kill" (1927). Phrase go along for the ride in the figurative sense "join in passively" is from 1956. A ride cymbal (1956) is used by jazz drummers for keeping up continuous rhythm, as opposed to a crash cymbal (ride as "rhythm" in jazz slang is recorded from 1936).