Divinity doctor singled out student at the beginning (9)
I believe the answer is:
godliness
'divinity' is the definition.
(thesaurus)
'doctor singled out student at the beginning' is the wordplay.
'doctor' indicates an anagram.
'at the beginning' says to take the initial letters.
The first letters of 'out student' is 'os'.
'singled'+'os'='singledos'
'singledos' anagrammed gives 'GODLINESS'.
(Other definitions for godliness that I've seen before include "borders on the hygienic?" , "'Cleanliness is akin to . . . . . . . . .'" , "Respectful behaviour" , "religion" , "reputedly close to being clean" .)