St. Stephen’s Day , proper n :
(Christianity) A Christian holiday commemorating Saint Stephen the protomartyr (first Christian martyr; died 34 C.E.), falling immediately after Christmas Day (on December 26 in the Western Church and on December 27 in the Eastern Orthodox Church).
Source http://handbookblogger.blogspot.com/2017/12/st-stephens-day-word-of-day-for.html
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