| Quadriplegie | quadriplegia |
| Quadrupede | quadruped |
| Quadrille | quadrille |
| Paraplegie | paraplegia |
| Quadrieren | quadrature |
| quadrieren | square |
| Quadrilliarde | octillion |
| Quadrupeder | quadruped |
| Quadratmeile | square mile |
| Quadriga | quadriga |
| Quadrillion | septillion |
| Quadrizeps | quadriceps |
| Quadrofonie | quadraphonic sound |
| Madrilenin | Madrilenian |
| Madrilene | Madrilenian Madrileño |
| Tetraplegie | quadriplegia |
| Audiologie | audiology |
| Mariologie | Mariology |
| Radiologie | radiology |
| Aquarianerin | aquarist |