Mammoth Uncensored Word List:
21 words ending with ma, 12 letters long

adenofibroma angiofibroma angiosarcoma chlorenchyma cystosarcoma dysgerminoma endothelioma fibrosarcoma glioblastoma histiocytoma hypersarcoma lymphadenoma lymphocytoma mesothelioma neurofibroma osteosarcoma plasmacytoma poikiloderma pseudomyxoma sclerenchyma ulocarcinoma