| Name | Meaning | Gender | Origin |
|---|
| Maxi | Pet form of names starting with Max | Unisex | English |
| Maximus | The greatest | Male | Latin |
| Midnight | Intense darkness, the middle of the night | Unisex | English |
| Mojo | Good luck charm. | Unisex | English |
| Monster | A creature of frightening appearance | Unisex | English |
| Monty | Gomeric's hill | Male | French |
| Moose | Largest member of the deer family. Moose have heavy brown bodies with humped shoulders and broad antlers. | Unisex | English |
| Ninja | | Unisex | Hebrew |
| Oscar | Divine spear | Male | English |
| Paisley | Church, cemetery | Unisex | English |
| Pea | | Unisex | Hebrew |
| Percy | Pierce valley | Male | French |
| Pinky | For Pinky Lee, the painting, and the color of her nose | Unisex | English |
| Pooh | | Unisex | Hebrew |
| Porky | | Unisex | Hebrew |
| Ralph | Wolf council | Male | Germanic |
| Rambo | | Unisex | Hebrew |
| Rebel | One that resists of defies authority | Unisex | English |
| Red | Red | Unisex | English |
| Rex | King | Male | Latin |
| Rocco | Battle cry | Male | Germanic |
| Rocky | Battle cry | Male | Germanic |
| Romeo | Pilgrim to Rome | Male | Italian |
| Rufus | Red | Male | Latin |
| Sable | Sable (black) | Unisex | English |
| Sammy | His name is God | Unisex | Hebrew |
| Sampson | Sun | Unisex | Hebrew |
| Samson | Sun | Male | Hebrew |
| Sarge | Noncommissioned Army or Air Force rank | Unisex | English |
| Sasha | Defending men | Unisex | Greek |