What is the deffense of duress also known as?

There is no other name for duress. Duress is the legal term in contract law. However, when the term is explained, it is explained as a form of coercion. Duress is often difficult to use a defense. To prove duress, you have to show that you were threatened into signing a contract. For instance, if your boss gave you a contract and told you that if you did not sign it that in turn you would be fired, then you could claim duress.