M. Weapons are tools that have mysterious and magic like properities. These are rare tools that are normally found and utilized by races other then Humans, i.e Dials in the Skypia Kingdom.
Mystic, Mystical, Magical or Mysterious weapons (often abbrivieated as M. Weapons) are tools used by the more minor races that inhabit the World. They are used as tools for everyday life or implements that are being exploited as weaponry for combat. They posses strange supernatural properties that can be compared to devil fruits.