ZOIC
| Date | Clue |
|---|---|
| 2016-06-14 | Geological period suffix |
| 2014-11-30 | End of an era? |
| 2010-01-31 | Suffix on era names |
| 2008-04-30 | Suffix with Meso- or Paleo- |
| 2004-01-18 | Suffix on era names |
| 2002-12-14 | Suffix in the names of many eras |
| 1999-10-20 | Suffix on era names |