abet (v.)

1590s, "the mutual pledging of things of value to be won or lost based on some future event," appearing simultaneously with the verb, originally in the argot of petty criminals, a word of unknown origin.

Perhaps it is a shortening of abet or else from obsolete beet "to make good" (related to better), if the original notion is "to improve" a contest by wagering on it, or to encourage a contestant. Or perhaps the word is from the "bait" sense in abet. The meaning "that which is wagered" is from 1796.

word-forming element expressing direction toward or in addition to, from Latin ad "to, toward" in space or time; "with regard to, in relation to," as a prefix, sometimes merely emphatic, from PIE root *ad- "to, near, at."

Simplified to a- before sc-, sp- and st-; modified to ac- before many consonants and then re-spelled af-, ag-, al-, etc., in conformity with the following consonant (as in affection, aggression). Also compare ap- (1).

In Old French, reduced to a- in all cases (an evolution already underway in Merovingian Latin), but French refashioned its written forms on the Latin model in 14c., and English did likewise 15c. in words it had picked up from Old French. In many cases pronunciation followed the shift.

Over-correction at the end of the Middle Ages in French and then English "restored" the -d- or a doubled consonant to some words that never had it (accursed, afford). The process went further in England than in France (where the vernacular sometimes resisted the pedantic), resulting in English adjourn, advance, address, advertisement (Modern French ajourner, avancer, adresser, avertissement). In modern word-formation sometimes ad- and ab- are regarded as opposites, but this was not in classical Latin.

Proto-Indo-European root meaning "to split," with derivatives in Germanic "referring to biting (hence also to eating and to hunting) and woodworking" [Watkins].

It forms all or part of: abet; bait (n.) "food used to attract prey;" bait (v.) "to torment, persecute;" bateau; beetle (n.1) "type of insect; bit (n.1) "small piece;" bite; bitter; bitter end; boat; boatswain; -fid; fissile; fission; fissure; giblets; pita; pizza; vent (n.).

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit bhinadmi "I cleave," Latin Latin findere "to split, cleave, separate, divide," Old High German bizzan "to bite," Old English bita "a piece bitten off, morsel," Old Norse beita "to hunt with dogs," beita "pasture, food."