( formal ) (used especially in negative sentences) to treat sb/sth without genuine respect :
He is not a person to be trifled with.
( formal ) (used especially in negative sentences) to treat sb/sth without genuine respect :
He is not a person to be trifled with.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005