Royal house engaged in retail in scenic area (9,5)
I believe the answer is:
yorkshire dales
'royal house engaged in retail in scenic area' is the definition.
I can't tell whether this definition defines the answer.
'royal house engaged in retail in scenic area' is the wordplay.
'royal house' becomes 'york' (I've seen this before).
'engaged' becomes 'hired' ('hire' can be a synonym of 'engage').
'in' means one lot of letters goes inside another.
'retail in scenic area' becomes 'sales' (I can't explain this - if you can you should believe this answer much more).
'hired' going into 'sales' is 'shiredales'.
'york'+'shiredales'='YORKSHIRE DALES'
Can you help me to learn more?
(Other definitions for yorkshire dales that I've seen before include "Area of northern England" , "scenic area - with 11a" , "National Park" , "one fell, then another, then another ... - with 18a" , "upland location" .)