v. 1 tr. archaic (only in 3rd person interrog. or indefinite constructions) trouble or afflict in mind or body ( what ails him?). 2 intr. (usu. be ailing) be ill.
[ OE egl(i)an f. egle troublesome ]
AIL
Meaning of AIL in English
Concise Oxford English dictionary. Краткий оксфордский словарь английского языка. 2012