The most common and most likely answer to this crossword clue is the 5 letter word ERATO
I've seen this crossword clue in Financial Times
E
R
A
T
O
More clues leading to the result ERATO
- Books are turning up inspirational source
- Returned books are an inspiration
- Cheers up in bedroom, regularly a source of inspiration
- Retroaction not oddly one to inspire
- Time after time, love is a poet’s inspiration
- One visiting writer at ode?
- English singer associated with Love andMuse
- On reflection, books are a source of inspiration
- Time to muse
- Revolutionary sailor inspired by old English muse
Buddy explains!
The straight part
We know that "Mythically one of nine" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case mythically one of nine = erato.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.