A moveable feast Meaning A feast day that falls on the same day of the week each year but which has a date which varies. Origin The Christian moveable (or movable) feasts are those holy days that are set by the date of Easter Sunday. Over the centuries there have been many disputes over how the date of Easter should be calculated, involving differing views concerning the calendar and religious observance. This rather complex canonical rule is the one used now in the Christian Church: [Easter Day is] the first Sunday following the first ecclesiastical full moon (which is the 14th day of an astronomical new moon) that occurs on or after the day of the Vernal Equinox (March 21st). Other religions also have holy days or feasts with variable dates and they have adopted the same term. Easter sets the date for numerous Christian feasts or fasts; for example: - Ash Wednesday: 46 days before Easter. This is the first day of Lent. - Shrove Tuesday: 47 days before Easter. This day is also known as Pancake Day in the UK and, in several places around the world, notably Rio de Janeiro and New Orleans, Mardi Gras (Fat Tuesday). - Pentecost: 49 days after Easter. This is also known, especially in the UK, as Whitsun. This name derives from White Sunday, making reference to the white robes worn by those who were baptized on the previous Easter. 'Moveable feast' has been adopted into the language as a metaphor for