MATER Meaning of MATER in English /may"teuhr/ , n. , pl. maters, matres /-treez/ . 1. Brit. Informal. mother 1 . 2. the backing holding the movable parts of an astrolabe. [ 1585-95; mater ] Random House Webster's Unabridged English dictionary. Полный английский словарь Вебстер - Random House . 2012