What is the legal term for a contract in which one party has not yet performed their obligations?

The legal term for a contract with performance still outstanding is an executory contract.

An executory contract has not been fully performed: one or both parties still have meaningful obligations to complete. A lease is a familiar example because the tenant may still owe rent and the landlord may still owe continuing possession or services. A purchase agreement can likewise remain executory before payment, delivery, or closing occurs.

The wording can cause a subtle mix-up. In many legal settings, especially bankruptcy, courts describe an executory contract as one in which performance remains due to some extent on both sides and a material failure by either party could excuse the other. If one party has completely performed and only the other has a remaining duty, some authorities may describe the contract as partially performed rather than executory. For a general trivia question, however, “executory contract” is the canonical term for an agreement whose obligations remain incomplete.

The opposite concept is an executed contract, in which the relevant parties have completed their required performance. “Executed” can also mean signed in ordinary conversation, so context matters: signing a contract does not necessarily mean its performance is complete.