In the Christian calendar, Maundy Thursday - also called Holy Thursday and, in the Eastern and Oriental Orthodox Churches, Great Thursday - is the feast or holy day on the Thursday before Easter that commemorates the Last Supper of Jesus Christ with the Apostles.
"Maundy Thursday" is the traditional name for this day in Britain and consequently is the usual name in Anglican and Presbyterian Churches worldwide. In other countries, "Holy Thursday" is the usual name among Roman Catholics. Lutherans use both names (see, for instance this site).
The word Maundy, used only in this context, is generally explained as derived, through Middle English, and Old French mandé, from Latin mandatum, the first word of the phrase "Mandatum novum do vobis ut diligatis invicem sicut dilexi vos" (A new commandment I give unto you, that you love one another as I have loved you) in the teaching by which Jesus drew out for the Apostles the significance of his action of washing their feet (John 13:34). Others see its origin in the word maund, derived from Old French mendier, which in turn comes from Latin mendicare (to beg). The name "Maundy Thursday" would thus have arisen in England because of the custom whereby each year on this day the sovereign gives alms to selected poor people in a container also called a "maund" or "maundy purse".

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