expansion card noun Computers. a card in a computer on which additional chips can be mounted to expand the computer’s capabilities.
Also called expansion board. Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019 expansion board in Science expansion board A printed circuit board that can be installed to enhance a computer’s capabilities, as by increasing memory or improving graphics. The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.