Mettelydd, n. a metallurgist
Mettelyddiaeth, n. mettellurgy
Mêth, n. a miss, abortion
Methadwy, a. fallible; perishable
Methdal, n. non-payment
Methedig, a. decayed; decrepit
Methedigaeth, n. failure: error
Methenw, n. a misnomer
Methiad, n. a failing, missing
Methiannu, v. to become failing