"proclamation or notice given in a church of an intended marriage," mid-15c. (late 12c. in Anglo-Latin), from Old English bannan "to summon, command, proclaim" (see ban (v.)). Also probably partly from Old French ban "announcement, proclamation, banns, authorization," from Frankish *ban or some other Germanic cognate of the Old English word. They were made part of ecclesiastic legislation 1215 by the fourth Lateran council.