v. phr. , informal To act excitedly and without careful thinking. John has gone off the deep end about owning a motorcycle. Mike warned his roommate not to go off the deep end and get married. Some girls go overboard for handsome movie and television actors.
GO OFF THE DEEP END
Meaning of GO OFF THE DEEP END in English
American idioms English vocabulary. Английский словарь американских идиом. 2012