St. Hilary's Day

St. Hilary's Day

January 13 or 14
St. Hilary of Poitiers (c. 315-c. 367) was a French theologian who, as bishop of Poitiers, defended the divinity of Christ against Arianism, which affirmed that Christ was not truly divine because He was a "created" being. The so-called "Hilary term," beginning in January at Oxford and Dublin universities, is named after him. At one time the phrase also referred to a term or session of the High Court of Justice in England. According to tradition St. Hilary's Day—observed on January 13 by Anglicans but on January 14 by Roman Catholics—is the coldest day of the year.
SOURCES:
DictDays-1988, p. 103
OxYear-1999, p. 33