Obscure eastern doctrine recollected (9)
I believe the answer is:
recondite
'obscure' is the definition.
('recondite' can be a synonym of 'obscure')
'eastern doctrine recollected' is the wordplay.
'eastern' becomes 'e'.
'recollected' indicates an anagram.
'e'+'doctrine'='edoctrine'
'edoctrine' anagrammed gives 'RECONDITE'.
(Other definitions for recondite that I've seen before include "(Of knowledge) obscure" , "Mysterious" , "Direct one to be obscure or difficult" , "Difficult to understand" , "Abstruse" .)