placentoma

noun
plac·​en·​to·​ma | \ ˌplas-ᵊn-ˈtō-mə How to pronounce placentoma (audio) \
plural placentomas also placentomata\ -​mət-​ə How to pronounce placentomata (audio) \

Medical Definition of placentoma

: a tumor developed from retained placental remnants