Skill of primarily kind old doctor in Cumbrian area (4-3)
I believe the answer is:
know-how
'skill' is the definition.
(I've seen this before)
'primarily kind old doctor in cumbrian area' is the wordplay.
'primarily' says to take the initial letters.
'old' becomes 'o' (abbreviation as in OT - Old Testament).
'doctor' becomes 'who' (as in the TV show Doctor Who).
'in' is an insertion indicator.
'cumbrian area' becomes 'NW' (North West of England).
The first letter of 'kind' is 'k'.
'o'+'who'='owho'
'owho' inserted inside 'nw' is 'nowhow'.
'k'+'nowhow'='KNOW-HOW'
'of' is the link.
(Other definitions for know-how that I've seen before include "Technique, expertise" , "Ingenuity - aptitude - knack" , "Practical knowledge or skill" , "Specialised skill" , "Ingenuity - experience" .)