| Answer | Crossword Clue |
|---|---|
| EON | Grand division of geological time. |
| EON | Longest division of geological time |
| ERA | Major division of geological time |
| AEON | Longest division of geological time |
| AEON | Longest division of geological time (var.) |
| AEON | Longest division of geological time (Var.) |
| EON | Geological time division |
| EON | Geological time division. |
| AEON | Geological time division |
| AEON | Geological time division (Var.) |
| EONS | Grand divisions of geological time. |
