There are 8 13-letter words that end with 'mas'.
| chlorenchymas | mesotheliomas |
| endotheliomas | glioblastomas |
| fibrosarcomas | neurofibromas |
| sclerenchymas | osteosarcomas |
Note: These 8 13-letter words that end with 'mas' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words end with omas, amas, emas, mmas, gmas, imas, umas, smas, rmas, ymas, hmas, lmas, tmas, cmas, dmas.
4-letter words end with 'mas' (1)