n. 底板, 母板

[计] 母板, 主板

motherboard \moth"er*board`\ n. (Electronics)
The board containing the main circuits of an electronic
device, especially computers. The term is used primarily in
microcomputer literature, where it designates the board
containing the main expansion bus, and usually also the cpu.
On motherboards designed with an expansion bus, often all of
the circuits not contained on an expansion card are on the
motherboard.
[PJC]