verb, -at⋅ed, -at⋅ing, adjective, noun | 1. | to collect or gather into a cluster or mass. |
| 2. | gathered together into a cluster or mass. |
| 3. | Botany. crowded into a dense cluster, but not cohering. |
| 4. | a mass of things clustered together. |
| 5. | rock composed of rounded or angular volcanic fragments. |