Little known about revolutionaries seizing queen (9)
I believe the answer is:
recherche
'little known' is the definition.
(recherche means exotic or obscure)
'about revolutionaries seizing queen' is the wordplay.
I cannot really see how this works, but
'about' could be 're' ('re' means regarding or about) and 're' is found within the answer.
'queen' could be 'er' (abbreviation for Elizabeth Regina) and 'er' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
(Other definitions for recherche that I've seen before include "Little-known" , "Rare or far-fetched, like her creche" , "Rare, exotic, obscure" , "Rare or exotic (French)" , "choice" .)