The term CARP, CARP, CARP can be broken down into three separate words: NAG (3 letters), ENDO (4 letters), and KOI (3 letters). NAG is an informal verb meaning to scold or complain persistently. ENDO is a shortened form of the word endodontics, which is a branch of dentistry that deals with the anatomy of the tooth and its associated structures. KOI is a type of ornamental fish native to East Asia that is often kept in outdoor ponds. Together, these three words form the term CARP, CARP, CARP, which is a type of freshwater fish found in Europe and Asia.