Mrs., a narrow-minded, conventional person who is extremely critical of any breach of propriety.
Origin of Grundy2
after Mrs. Grundy, a character mentioned in the play Speed the Plough (1798) by Thomas Morton (1764?–1838), English playwright
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a narrow-minded person who keeps critical watch on the propriety of others
Word Origin for Grundy
C18: named after Mrs Grundy, the character in T. Morton's play Speed the Plough (1798)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012