What a grenade says to cut you off from taking her home, typically in a bar scenario, so she feels better about herself, even though she's a grenade and will never get laid with this fruitless tactic. Smarter women will trap you in a lie or convince you to say something off-putting to weed out the clowns rather than leaning on the never clever Just Say No method learned from the D.A.R.E. program taught to them in elementary school. No means no can also be used as an adjective to describe grenades of this type, for example as a no-means-no grenade instead of a supergrenade or slutty grenade. It can also be used to warn your bros by loudly exclaiming to your fellow buddies "No means no, bro!" while in the company of women or while your best friend is attempting to take one home.
Dude: Let's go back to my place.
Chick: No means no, sir.
Dude: Whatever, grenade...