There are 14 words that start with 'ephem'.
| ephemera | ephemerae |
| ephemeral | ephemeras |
| ephemerid | ephemeris |
| ephemeron | ephemerals |
| ephemerids | ephemerons |
| ephemerally | ephemerides |
| ephemerality | ephemeralities |
Note: These 14 words that start with 'ephem' are found from the USA & Canada version of the tournament Scrabble word list.