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expansion slot

American  

noun

Computers.
  1. a connection in a computer, especially a personal computer, to which a new board or card can be added to expand the computer's capabilities.


expansion slot British  

noun

  1. a physical electronic interface provided in a computer system to enable extra facilities to be added easily at a later date

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of expansion slot

First recorded in 1980–85