Definition of don't tell me
1 —used to request that someone not give one information because one wants to guess what it is "I know the answer." "Don't tell me. I want to guess."
2 informal —used to show that one already knows what someone is going to say especially because he or she often says such things "I have a favor to ask of you." "Don't tell me—I bet you need to borrow more money, don't you?"
3 informal —used to express surprise and disappointment "Don't tell me the concert tickets were all sold out?!" "No, I bought the last two tickets."
Love words? Need even more definitions?Merriam-Webster unabridged
Words at Play
Ask the Editors