1911 Encyclopædia Britannica/Low Sunday

LOW SUNDAY, the first Sunday after Easter, so called because of its proximity to the “highest” of all feasts and Sundays, Easter. It was also known formerly as White Sunday, being still officially termed by the Roman Catholic Church Dominica in albis, “Sunday in white garments,” in allusion to the white garments anciently worn on this day by those who had been baptized and received into the Church just before Easter. Alb Sunday, Quasimodo and, in the Greek Church, Antipascha, and ἡ δευτεροπρώτη Κυριακή (literally “second-first Sunday,” i.e. the second Sunday after the first) were other names for the day.