- A circuit board which is plugged into the bus or an expansion slot of a computer, in order to add functions or resources. common examples include graphics accelerators, sound cards, and Ethernet adapters. Also called by various other terms, including expansion board, accessory card, add-on board, adapter card, card (1), adapter (3), and add-on.
- synonymexpansion board
- noun a small device that can be inserted into a computer to improve its memory or other capabilities, such as a sound card
- noun a printed circuit board connected to a system to increase its functions or performance.