A Christian holy day (December 28) commemorating the massacre of the Holy Innocents, young boys killed by King Herod.
From Old English 'cildra' (children) + 'mas' (mass). The holiday name literally means 'children's mass' and dates to medieval Christian practice honoring the innocent children slaughtered in Bethlehem.
Childermas was considered so unlucky in medieval times that people avoided starting any important tasks or projects on that day—Shakespeare mentions this superstition—yet it commemorates one of Christianity's darkest stories of innocent child death.
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