allure v.

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.

early 14c., "something which allures or entices, an attraction" (a figurative use), originally the name of a device for recalling a hawk, from Anglo-French lure, Old French loirre "device used to recall hawks, lure," from Frankish *lothr or some other Germanic source, from Proto-Germanic *lothran "to call" (source also of Middle High German luoder, Middle Low German loder "lure, bait," German Luder "lure, deceit, bait;" also Old English laþian "to call, invite," German laden "invite, summon").

The original lure was a bunch of feathers, arranged so as to resemble a bird, on a long cord, from which the hawk was fed during its training. Used of means of alluring other animals (especially fish) from c. 1700. Technically, bait (n.) is something the animal could eat; lure is a more general term. Also in 15c. a collective word for a group of young women (as a c. 1400 document has it, "A lure of ffaukones & damezelez").