What defines a market situation where there is only one seller of a particular good or service?

The term that defines a market situation where there is only one seller of a particular good or service is known as a monopoly. In a monopoly, the single seller has significant control over the market and can influence prices and supply without direct competition. This market structure allows the monopolist to set prices higher than in competitive markets because consumers have no alternative providers for the product or service in question.

The characteristics of a monopoly include barriers to entry for potential competitors, unique products with no close substitutes, and a high degree of market power. Understanding monopolies is crucial for ethical procurement and supply practices, as they can lead to price manipulation and reduced consumer choice, raising concerns about fairness and competition in the marketplace.