What does Boxing Day have to do with boxing?
late 14c., originally ecclesiastical, from Latin censura "judgment, opinion," also "office of a censor," from census, past participle of censere "appraise, estimate, assess" (see censor (n.)). General sense of "a finding of fault and an expression of condemnation" is from c.1600.
1580s, from censure (n.) or else from French censurer, from censure (n.). Related: Censured; censuring.
Such men are so watchful to censure, that the have seldom much care to look for favourable interpretations of ambiguities, to set the general tenor of life against single failures, or to know how soon any slip of inadvertency has been expiated by sorrow and retractation; but let fly their fulminations, without mercy or prudence, against slight offences or casual temerities, against crimes never committed, or immediately repented. [Johnson, "Life of Sir Thomas Browne," 1756]