A man uses a magnetic card to open a hotel room door.
magnetic card definition by American Heritage Dictionary
nounThe American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
A card, such as a bank card for use in an automated teller machine, that has a magnetizable strip or surface on which data can be recorded.