Tweedy fellow splitting hairs about what's right (6)
I believe the answer is:
harris
'tweedy fellow' is the definition.
The definition suggests a singular noun which matches the answer.
'splitting hairs about what's right' is the wordplay.
'splitting' is an insertion indicator (some letters split a word into two).
'about' is an anagram indicator.
'what's right' becomes 'r' (common abbreviation).
'hairs' anagrammed gives 'haris'.
'haris' placed around 'r' is 'HARRIS'.
Can you help me to learn more?
(Other definitions for harris that I've seen before include "boating man" , "Isle known for tweed" , "location off Scottish mainland" , "Hebridean area associated with tweed" , "Joel Chandler --, creator of Brer Rabbit" .)