Maundy Thursday
noun
Maun·dy Thursday ˈmȯn-dē- 
ˈmän-
: the Thursday before Easter observed in commemoration of the institution of the Eucharist
Word History
Etymology
Middle English maunde ceremony of washing the feet of the poor on Maundy Thursday, from Anglo-French mandet, from Latin mandatum command; from Jesus' words in John 13:34 — more at mandate
First Known Use
15th century, in the meaning defined above