abate 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.

"strike repeatedly, beat violently and rapidly," early 14c., from Old French batre "to beat, strike" (11c., Modern French battre "to beat, to strike"), from Latin battuere, batuere "to beat, strike," a rare word in literary Latin but evidently an old one and popular in Vulgar Latin. It is said to be probably borrowed from Gaulish (compare Welsh bathu "beat," Irish and Gaelic bat, bata "staff, cudgel") and to be perhaps from PIE root *bhau- "to strike." (source also of Welsh bathu "beat;" Old English beadu "battle," beatan "to beat," bytl "hammer, mallet").

The word began to be widely used in reference to domestic abuse in 1962. Related: Battered; battering. Battering-ram is an ancient weapon (Latin aries), but the phrase is attested only from 1610s.