Related Clues:
- Very long time unit
- Quite a long time
- It's longer than an era
- Big time division
- Span of epoch proportions?
- Millennium, to Miss Marple
- Geological range
- 2005 role for Charlize
- Ages and ages and ages
- Extensive period
- Immeasurable time
- Geologicial time period
- Billion-year time period
- One billion years, geologically
- Humongous span