Meaning

noun a public ceremony on Maundy Thursday when the monarch distributes Maundy money

originFrom Middle English maundee, maunde, from Old French mandée (“mandated”), from Latin mandatum (“commandment”). Doublet of mandate. The word came to refer to the foot-washing ceremony performed on Thursday before Easter because of the phrase used by Jesus to explain his act of foot-washing, which in the Latin Vulgate begins: Mandatum novum do vobis ut diligatis invicem ..., i.e. "A new commandment…

Etymology from Wiktionary, CC BY-SA 3.0