Maun ‧ dy Thurs ‧ day /ˌmɔːndi ˈθɜːzdi, -deɪ $ ˌmɒːndi ˈθɜːrz-/ BrE AmE noun [uncountable]
[ Date: 1200-1300 ; Origin: maundy 'Christian ceremony of washing poor people's feet' , from Old French mandé , from Latin mandatum 'command' ]
the Thursday before Easter