Schoolmasterly (8)
I believe the answer is:
pedantic
'schoolmasterly' is the definition.
(thesaurus)
This is the entire clue.
(Other definitions for pedantic that I've seen before include "Excessively concerned with minor details" , "Insisting on sticking stricktly to the rules" , "Overly concerned with insignificant detail" , "Precise; didactic" , "quibbling" .)