Settled soon astride horse of French revolutionary (9)
I believe the answer is:
inhabited
'settled' is the definition.
(similar in meaning)
'soon astride horse of french revolutionary' is the wordplay.
'soon' becomes 'inabit' (I've seen this in another clue).
'astride' is an insertion indicator.
'horse' becomes 'H' (abbreviation as in horse power).
'of french' becomes 'de' ('of' in French).
'revolutionary' says the letters should be written backwards (letters revolve around).
'de' reversed gives 'ed'.
'inabit' going around 'h' is 'inhabit'.
'inhabit'+'ed'='INHABITED'
(Another definition for inhabited that I've seen is " Dwelled in".)