a credit card issued in conjunction with an organization, as a university or sports club.
Origin of affinity card
First recorded in 1985–90
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British a credit card issued by a bank or credit-card company, which donates a small percentage of the money spent using the card to a specified charity
US a card entitling members of an affinity group (e.g. club, college) to a discount when used for purchases
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