1) November observance 2) The first Sunday in Advent 
Advent Sunday is the first day of the liturgical year in the Western Christian churches. It also marks the start of the season of Advent. In the Roman Catholic, Lutheran, Anglican, and Methodist churches the celebrant wears violet-coloured or blue vestments on this day, and the first violet or blue Advent candle is lit at Mass. In the Church of Sw...
[n] - the first of four Sundays of Advent
noun the first of the four Sundays during Advent
the first Sunday in Advent.