No Shit, Sherlock Definition

Origin of No Shit, Sherlock

• no shit (“an expression of amazement") + Sherlock (“a fictional detective who makes ingenious deductions")An expression of amazement followed by comparing the interlocutor to the detective Sherlock Holmes , as if they have just made a great deduction . This expression is, however, used sarcastically, to point out that the interlocutor merely stated the obvious.

  From Wiktionary