Related Clues:
- Long geologic time division
- Ages disguising son behind Egyptian leader
- Nearly infinite perioD
- Immense time spans
- A long, long, long time
- Huge amount of 50-Across
- A gazillion years, seemingly
- Seemingly endless time
- Many a doctor's office wait, seemingly
- Nose (anag)
- Units on the geologic time scale
- Long, long stretches
- Billion-year span
- Not just centuries
- Twenty bajillion years