Etymology: < Anglo-Norman abeite, abette, abett, Anglo-Norman and Old French, Middle French abet deception, trickery (late 12th cent.), incitement (13th cent.) < abeter abet v. Compare post-classical Latin abettum instigation, abetment (frequently from 1247 in British sources; < Anglo-Norman and Old French).

Etymology: < Anglo-Norman abbeter, abetter, abbetter, abeter , Anglo-Norman and Old French, Middle French abeter to scheme (late 12th cent. in Anglo-Norman), to provoke (a person) (c1232), to trick, deceive (early 13th cent.), to excite, incite (13th cent.), to incite (a person) to unlawful action (14th cent. in Anglo-Norman) < a- a- prefix⁵ + beter to fight, bait (e.g. a bear) (late 12th cent.), to pursue, harass (early 13th cent.), probably a borrowing of a form in a West Germanic language < the same base as Old English bǣtan and Old Icelandic beita to cause to bite (see bait v.). Compare Old Occitan abetar to deceive, cajole (13th cent.), and also post-classical Latin abettare (also abbettare) to incite (frequently from c1290 in British sources).In sense 3 either showing use of the present word influenced by association with bet v., or perhaps showing a separate formation < (perhaps) a- prefix⁵ + bet v.