teach grandmother to suck eggs


Also found in: Dictionary, Thesaurus, Legal, Encyclopedia.

teach (one's) grandmother to suck eggs

To try to teach an older person who is wiser and more experienced and worldly than a young person may think. Why are you explaining basic typing to Ethel? Yes, she's 70, but she's been using a computer since before you were born—quit teaching your grandmother to suck eggs.
See also: egg, grandmother, suck, teach

teach one's grandmother to suck eggs

Fig. to try to tell or show someone more knowledgeable or experienced than oneself how to do something. Don't suggest showing Mary how to knit. It will be like teaching your grandmother to suck eggs. Don't teach your grandmother to suck eggs. Bob has been playing tennis for years.
See also: egg, grandmother, suck, teach