pron. (obj. whomever or colloq. whoever; poss. whosever) 1 the or any person or persons who (whoever comes is welcome). 2 though anyone (whoever else objects, I do not; whosever it is, I want it). 3 colloq. (as an intensive) who ever; who at all (whoever heard of such a thing?).
WHOEVER
Meaning of WHOEVER in English
Concise Oxford English dictionary. Краткий оксфордский словарь английского языка. 2012