{v. phr.}, {informal} To speak carelessly and rudely; hurt another's feelings without intending to; make a rude mistake. * /He put his foot in it with his remark about self-made men because Jones was one of them./ * /She put her foot in her mouth with her joke about that church, not knowing that one of the guests belonged to it./
PUT ONE'S FOOT IN ONE'S MOUTH
Meaning of PUT ONE'S FOOT IN ONE'S MOUTH in English
Dictionary of English idioms . Словарь английских идиом. 2012