The most common and most likely answer to this crossword clue is the 8 letter word ROUSSEAU
I've seen this crossword clue in The Times
R
O
U
S
S
E
A
U
More clues leading to the result ROUSSEAU
- French philosopher has no truck at first for union stuff
- Philosopher arouses university reforms
- USA sure to get excited about old philosopher
- French painter unexpectedly arouses you at the climax
- Regret in this way that’s pronounced in philosopher
- Philosopher offers wine and gold, when entertaining us
- Artist‘s model clears bottom drawer
- Painter appears in sombrero, usually
- Regret very much listening to influential thinker
- Regret very much in hearing influential thinker
Buddy explains!
The straight part
We know that "philosopher" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case philosopher = rousseau.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.