Which legal term describes when one party fails to meet their contractual obligations?

The correct legal term that describes when one party fails to meet their contractual obligations is "Breach of contract." This term is foundational in contract law and refers specifically to a situation where one of the parties to an agreement does not perform their duties as outlined in the contract. A breach can occur in various forms, such as failing to deliver goods, not paying on time, or not performing as promised.

Understanding the implications of a breach is vital, as it entitles the non-breaching party to seek remedies, which may include damages or specific performance. This concept is key in guiding parties to fulfill their contractual duties and addressing the consequences when they do not. The other terms, such as delegation (which involves a party transferring their obligations to another party), subrogation (a legal process allowing one party to step into the shoes of another to pursue a claim), and mitigation (the duty to minimize losses after a breach occurs), serve different functions within the scope of contract law and do not define the failure to meet contractual obligations themselves.