A backplane is an electronic circuit board containing circuitry and sockets into which additional electronic devices on other circuit boards or cards can be plugged; in a computer, generally synonymous with or part of the motherboard
WhatIs.com (A knowledge exploration and self-education tool about information technology IT), Margaret Rouse (Editorial Director), Electronics Glossary, TechTarget, Inc., USA 2015. http://whatis.techtarget.com/glossary/Electronics/ page/2, (Electr - Amer) {992}