A computer’s main, and typically, largest printed circuit board. The central processing unit (CPU) chip, read-only memory (ROM), random-access memory (RAM) are located on this board. Other major functional elements, and in PCs, the basic input output system (BIOS) are also located there. It has sockets to plug in other circuits boards, known as daughter boards, like communication ports and peripheral devices. Nearly every electronic device has a main circuit board referred to also as a motherboard . Also known as system board.
Black’s Law Online Dictionary
