1 definition by Ms. Fiddly Bums

noun: A secret, usually prepaid, cell phone used by both males and females whom are having an affair in order to keep their normal cell phones free of evidence of the affair.
Woman #1: "I think my husband is cheating on me, but I checked his cell phone records and couldn't find any strange numbers on it".

Woman #2: "You might want to search his drawers for a dirty phone that he could be using instead".
by Ms. Fiddly Bums March 31, 2009
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