heteromorphosis

noun
het·​ero·​mor·​pho·​sis | \ -ˈmȯr-fə-səs also -mȯr-ˈfō-\
plural heteromorphoses\ -​ˌsēz How to pronounce heteromorphoses (audio) \

Medical Definition of heteromorphosis

1 : the production in an organism of an abnormal or misplaced part especially in place of one that has been lost (as the regeneration of a tail in place of a head)
2a : the production of a malformed or malposed tissue or organ
b : the formation of tissue of a different type from that from which it is derived