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card tart

British  

noun

  1. informal a credit-card holder who continually changes providers, transferring his or her balance to another provider whenever the agreed period of low interest on the prior loan is about to expire

"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