Advent is a season observed in most Christian denominations as a time of waiting and preparation for both the celebration of Jesus's birth at Christmas and the return of Christ at the Second Coming. It begins on the fourth Sunday before Christmas, often referred to as Advent Sunday.
Advent, (from Latin adventus, “coming”), in the Christian church calendar, the period of preparation for the celebration of the birth of Jesus Christ at Christmas and also of preparation for the Second Coming of Christ.