The Collaborative International Dictionary
Childermas day
Childermas day \Chil"dermas day`\ [AS. cildam[ae]sse-d[ae]g; cild child +d[ae]g day.] (Eccl.) A day (December 28) observed by mass or festival in commemoration of the children slain by Herod at Bethlehem; -- called also Holy Innocent's Day.