Which term refers to the amount actually paid in a particular transaction?

The term that refers to the amount actually paid in a particular transaction is "market price." Market price reflects the actual transaction value between buyers and sellers, encompassing the specific negotiated amount agreed upon for a definite exchange of goods or services. This term captures the real-world aspect of transactions, as it is not an estimate or appraisal but rather the genuine amount transferred during the sale.

In contrast, the concept of "value in exchange" typically refers to the worth of an item in the marketplace and does not necessarily reflect the precise amount paid in a specific transaction. "Historical cost" pertains to the original acquisition cost of an asset, which may not correspond to what it could sell for today. "Market value" is an estimate of the likely price an asset would fetch in the marketplace under normal conditions, also not confined to a particular transaction but rather based on broader trends and assessments of worth.