Idiom of the day :- Riff-raff

Usage, examples and definition of the Idiom :-

Undesirable and untrustworthy people who are of a low social class A : Would you like to go to the Queen’s Head pub ? B : I don’t think so. It seems to attract all kinds of riff-raff. Why on earth do you want to go ? A : I’m meeting my friends there ! This word is normally used to refer to a group of people. Its origin is the Old French expression rif et raf which meant everyone / one and all.