adulteryyoudaoicibaDictYouDict[adultery 词源字典]
adultery: [14] Neither adultery nor the related adulterate have any connection with adult. Both come ultimately from the Latin verb adulterāre ‘debauch, corrupt’ (which may have been based on Latin alter ‘other’, with the notion of pollution from some extraneous source). By the regular processes of phonetic change, adulterāre passed into Old French as avoutrer, and this was the form which first reached English, as avouter (used both verbally, ‘commit adultery’, and nominally, ‘adulterer’) and as the nouns avoutery ‘adultery’ and avouterer ‘adulterer’.

Almost from the first they coexisted in English beside adult- forms, deriving either from Law French or directly from Latin, and during the 15th to 17th centuries these gradually ousted the avout- forms. Adulter, the equivalent of avouter, clung on until the end of the 18th century, but the noun was superseded in the end by adulterer and the verb by a new form, adulterate, directly based on the past participle of Latin adulterāre, which continued to mean ‘commit adultery’ until the mid 19th century.

=> alter[adultery etymology, adultery origin, 英语词源]
adultery (n.)youdaoicibaDictYouDict
"voluntary violation of the marriage bed," c. 1300, avoutrie, from Old French avouterie (12c.), noun of condition from avoutre, from Latin adulterare "to corrupt" (see adulteration). Modern spelling, with the re-inserted -d-, is from early 15c. (see ad-).

In Middle English, also "sex between husband and wife for recreational purposes; idolatry, perversion, heresy." Classified as single adultery (with an unmarried person) and double adultery (with a married person). Old English word was æwbryce "breach of law(ful marriage)" (compare German Ehebruch). Adultery Dune in Arizona corresponds to Navajo sei adilehe "adultery sand," where illicit lovers met privately.