fictional English character who typifies the censorship enacted in everyday life by conventional opinion. She first appears (but never onstage) in Thomas Morton's play Speed the Plough (produced 1798), in which one character, Dame Ashfield, continually worries about what her neighbour Mrs. Grundy will say of each development. Since then the term Mrs. Grundy has passed into everyday speech as a criterion of rigid respectability, especially in contexts in which free expression is impeded by excessive purity.