What are adapter boards or interface cards placed into expansion slots called?

Adapter boards or interface cards that are placed into expansion slots are commonly referred to as "cards." This term encompasses a wide range of add-on components that enhance or enable specific functionalities within a computer system.

These cards are designed to be inserted into the expansion slots on a motherboard, allowing the system to interface with different types of hardware or peripherals, such as graphics cards, sound cards, or network interface cards. Each type of card serves a unique purpose, enhancing the capabilities of the computer by providing additional features or improving performance.

While "modules" might sound plausible, this term usually refers to a complete unit or component designed to perform a specific function within a larger system and is not as precisely defined as "cards" in the context of computer expansion slots. "Processors," on the other hand, refer specifically to the central processing unit (CPU) of the computer, which is quite different from the expansion cards that can be added. "Connectors" refer to the physical interfaces that allow different components or devices to link with one another, rather than the cards themselves that provide function within the system.