Magnate vs. Magnet
Magniloquent vs. Grandiloquent
Mail vs. Male
Maine vs. Main
Maize vs. Maze
Mall vs. Maul
Manor vs. Manner
Mantel vs. Mantle
Many vs. Much
Martial vs. Marital
Marshal vs. Martial
Masterly vs. Masterful
Material vs. Materiel
Maxim vs. Axiom
Mayoralty vs. Mayoral
Mean vs. Mien
Meander vs. Maunder
Meanwhile vs. Meantime
Medal vs. Meddle
Media vs. Medium