Jury nullification refers to a jury's knowing and deliberate rejection of the evidence or refusal to apply the law either because the jury wants to send a message about some social issue that is larger than the case itself, or because the result dictated by law is contrary to the jury's sense of justice, morality, or fairness.

It's a bit more complex and broad than that.

Its the jury disagreeing with the law

Jury nullification is exercised by juries finding defendants not guilty