| Quadratum | quadrate bone |
| Quadratur | quadrature |
| Quadrat- | square |
| Quadrat | square |
| Quadratfuß | square foot |
| Quadrant | quadrant |
| Quadrivium | quadrivium |
| Quantum | quantum |
| Quart | quart |
| Quartil | quartile |
| Aquarium | aquarium tank |
| Quadratzahl | square number |
| Quadriga | quadriga |
| Quadrille | quadrille |
| Quartal | quarter |
| Quartär | Quaternary |
| quadratisch | quadratic square |
| Superatom | superatom |
| Erratum | erratum |
| Adlatus | assistant |