What is Candlemas-Day?

Legal Definition
In English law. A festival appointed by the church to be observed on the second day of February in every year, in honor of the purification of the Virgin Mary, being forty days after her miraculous delivery. At this festival, formerly, the Protestants went, and the Papists now go, in procession with lighted candles ; they also consecrate candles on this day for the service of the ensuing year. It is the fourth of the four cross quarter-days of the year. Wharton
-- Black's Law Dictionary