| Name | Meaning | Gender | Origin |
|---|
| Mau | | Unisex | |
| Max | Large spring | Male | English |
| Max | Large spring | Male | English |
| Maya | Abbreviation of Amalia: variant of Maia.
| Female | Hebrew |
| Mayo | yew-tree plain | Male | Irish |
| Melon | | Unisex | |
| Merlin | Character on Chocolate Frog card.
| Male | Welsh |
| Mia | Mine | Female | Scandinavian |
| Mickey | Abbreviation of Michael and Micah Who is like God?
| Male | English |
| Midnight | Intense darkness, the middle of the night | Male | English |
| Mikey | | Unisex | |
| Millie | English, gentle strength | Female | English |
| Milo | Merciful.
| Male | Latinized |
| Milo | Merciful.
| Male | Latinized |
| Mimi | Form of Williamina
| Female | English |
| Mimi | Form of Williamina
| Female | English |
| Minette | Form of Williamina
| Female | |
| Minka | Strong | Male | German |
| Minnie | Form of Williamina
| Female | English |
| Minou | | Unisex | |
| Miss Kitty | | Unisex | |
| Missy | Informal term for young woman | Female | English |
| Misty | misty.
| Female | English |
| Misty | misty.
| Female | English |
| Mittens | | Unisex | |