A clause that can be invoked when you and your significant other have had no form of contact for ten days. When you two haven't talked, kissed, had sex, or any variation of the three, for that specific length of time, it's not considered cheating if you hook up with someone else. It's considered substitution.
"You dick, how could you cheat on me?"
"Shut up, bitch. Don't you know about the ten day no-contact clause?"