The old expression “Типун тебе на язык” ("Tipun tebe na yazyk" or literally "I wish you had a pimple on your tongue!") The ‘Phraseological Dictionary of the Russian Language’ defines it as "an unkind wish to someone who says things that should not be said". To put it simply, "Tipun tebe na yazyk" can be said instead of "You'd better keep silent!" It was an old Russian way of a “tongue-lashing”. I wish you had a pimple on your tongue!