The buyer in a contract is called the:

In real estate and contract law, the buyer in a contract is specifically referred to as the "vendee." This term is derived from old French and is prominently used in legal documents to delineate the party purchasing the property. The vendee is responsible for fulfilling the terms of the contract, such as making payment and adhering to any conditions stipulated.

The other terms provided have different meanings within the context of real estate transactions. The seller, for instance, is the "vendor," who is the party transferring ownership of the property to the buyer. "Negociant" typically refers to a merchant or dealer, particularly in wine, and is not directly applicable in real estate transactions. Therefore, understanding these distinctions is crucial for effectively navigating and discussing real estate contracts.