| Madeline | woman from Magdala, one who is elevated, a high tower | Female | English |
| Madonna | my lady | Female | Latin |
| Magic | Possessing qualities that produce baffling effects | Male | Word |
| Magic | Possessing qualities that produce baffling effects | Male | Word |
| Magnolia | Flower
| Female | Latin |
| Magpie | | Unisex | |
| Mahon | Bear | Unisex | Irish |
| Maia | nurse, mother, goddess of spring; great | Female | Greek |
| Malvina | Smooth Brow | Female | Celtic |
| Mannikin | | Unisex | |
| Mansfield | From The Field By The Small River | Unisex | English |
| Marble | | Unisex | |
| Marco Polo | | Unisex | |
| Marcus | warlike | Male | Latin |
| Margaret | after Margaret Thatcher | Female | Greek |
| Marilyn | bitter | Female | English |
| Marley | From the lake in the meadow | Female | English |
| Marley | From the lake in the meadow | Female | English |
| Marshal Jake | | Unisex | |
| Marshmallow | A soft spongy sweet confectionery. Also a timid person. | Unisex | |
| Marshmellow | | Unisex | |
| Marvel | To Wonder, Admire | Female | French |
| Marzipan | from the Flash cartoon Homestar Runner | Unisex | |
| Mascara | | Unisex | |
| Mashed Potatoes | | Unisex | |