mastocytoma

noun
mas·​to·​cy·​to·​ma | \ ˌmas-tə-ˌsī-ˈtō-mə How to pronounce mastocytoma (audio) \
plural mastocytomas also mastocytomata\ -​mət-​ə How to pronounce mastocytomata (audio) \

Medical Definition of mastocytoma

: a tumorous mass produced by proliferation of mast cells