| Term | Definition | Contributor | Modified |
|---|---|---|---|
| Rodolicoite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Roeblingite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Roedderite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Roemerite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Roentgen rays | No definition provided | Christopher Rauch | 2023.12.01 |
| Roesslerite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Rogerenes | No definition provided | Christopher Rauch | 2023.12.01 |
| Roggianite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Rogues and vagabonds | No definition provided | Christopher Rauch | 2023.12.01 |
| Rohaite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Rók stone inscription | No definition provided | Christopher Rauch | 2023.12.01 |
| Rokuehnite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Rokuhnite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Role | The assigned or assumed function or positionof an individual. | Ryan McGranaghan | 2023.04.16 |
| Role | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Role of fluids | No definition provided | Ryan McGranaghan | 2023.04.16 |
| roll | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Rollandite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| roll cloud | A low-level, horizontal, tube-shaped arcus cloud associated with a gust front of a convective storm or occasionally a cold front. | Ryan McGranaghan | 2023.04.16 |
| Roller polo | No definition provided | Christopher Rauch | 2023.12.01 |