"Maundy Thursday" is the traditional name for this day in England. It is therefore the usual name also in English-speaking Protestant Churches that originated in that country and even in some that originated in Scotland, although the Scottish Book of Common Prayer uses the name "Holy Thursday". Other English-speaking Protestant Churches, such as the Lutheran, use both "Maundy Thursday" and "Holy Thursday". Among Roman Catholics, except in England, the usual English name for the day is "Holy Thursday", in line with the name used in major Romance Languages. Presumably these modern names came into being before the Catholic Church changed the pagan names of the days of the week in Latin.
The word Maundy is derived through Middle English, and Old French mandé, from the Latinmandatum, the first word of the phrase "Mandatum novum do vobis ut diligatis invicem sicut dilexi vos" ( A new commandment I give unto you, That ye love one another; as I have loved you), the statement by Jesus in the Gospel of John (13:34) by which Jesus explained to the Apostles the significance of his action of washing their feet. The phrase is used as the antiphon sung during the "Mandatum" ceremony of the washing of the feet, which may be held during Mass or at another time as a separate event, during which a priest or bishop (representing Christ) ceremonially washes the feet of others, typically 12 persons chosen as a cross-section of the community.