| Name | Meaning | Gender | Origin |
|---|
| Leith | A harbour in Scotland | Male | Gaelic |
| Liberty | Freedom | Female | Latin |
| Lincoln | Lake settlement, lake colony | Male | English |
| Lynn | Dwells By The Torrent | Female | English |
| Madison | Son of Maud | Unisex | English |
| Magnus | Great | Male | Latin |
| Margaret | Pearl | Female | Greek |
| Mariana | Latinate form of Marian | Female | Latin |
| Marin | From the god Mars | Unisex | Latin |
| Marina | From the god Mars | Female | Latin |
| Maris | Of the Sea | Female | Latin |
| Marlin | A Form Of Merle. | Unisex | English |
| Marlow | Drained lake | Male | English |
| Maxwell | Maccus's stream | Male | English |
| Maya | Uncertain, perhaps mother or great one | Female | Greek |
| Meri | Mirthful: Joyous. Also An Abbreviation Of Meredith. | Unisex | English |
| Misty | Misty | Female | English |
| Moana | The sea | Female | Pacific Islander |
| Molly | Uncertain, maybe bitter | Female | Hebrew |
| Monroe | Mouth of the River Roe | Male | Gaelic |
| Moon | Letters | Female | Korean |
| Morgan | Uncertain, perhaps bright sea | Female | Welsh |
| Mortimer | Dead sea | Male | French |
| Morwen | Maid | Female | Welsh |
| Morwenna | Maid | Female | Welsh |
| Moss | Drawn out of the water | Male | Hebrew |
| Muriel | Bright as the sea | Female | Gaelic |
| Murphy | Sea warrior | Male | Gaelic |
| Murray | Man of the sea | Male | Gaelic |
| Myrtle | Myrtle | Female | English |