What term describes a material that resists the passage of an electric current?

The term that describes a material that resists the passage of an electric current is "insulator." Insulators are materials that do not allow electric charge to flow through them easily due to their high resistance. Common examples of insulators include rubber, glass, and plastic. These materials are often used to coat or surround conductive materials to prevent unwanted flow of electricity, thus ensuring safety and efficiency in electrical applications.

In contrast, conductors, such as copper and aluminum, allow electric current to flow freely. Transmitters and receivers are terms that relate to the sending and receiving of signals, typically in communication systems, rather than the ability to resist electrical current. Hence, the correct identification of insulators is important for understanding electrical safety and circuit design.