Adulter, the equivalent weight of avouter, clung on until the cease of the 18th century, merely the noun was superseded in the oddment by fornicator and the verb by a recently form, adulterate, direct based on the yesteryear participle of Italic adulterare, which continued to signify 'put adultery' until the mid 19th century. More or less take suggested "grown children" and "grown-up children", simply since the 1970s "adult children" has been the prevalent phrase both in Brits West Germanic an...