/ˈnɒkaʊt ruːl/ – Phrase
Definition: Quy tắc loại trừ.
A more thorough explanation: the principle in contract law that where terms and conditions that are included on various forms, letters, laws, and agreements used to establish the provisions of a contract in a so-called battle of forms do not agree, those terms cancel each other out and are dropped from the contract. NB battle of forms happens where each party tries to argue that its own terms and conditions have been incorporated into the contract. This can happen when multiple documents, often containing boilerplate terms.
Example: The merger agreement includes a knockout clause that will terminate the deal if either party enters into a competing merger agreement.