(Mrs.). A type of female backbiters. In Sheridan's comedy of The School for Scandal.
“The name of `Mrs. Candour' has become one of those formidable by-words, which have had more power in putting folly and ill-nature out of countenance than whole volumes of remonstrance.” —T. Moore.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894