Of noble mountain stock? (8)
I believe the answer is:
highborn
'of' is the definition.
The definition and answer are not the same part of speech.
'noble mountain stock?' is the wordplay.
'noble' becomes 'high' (I've seen this in another clue).
'mountain stock?' becomes 'born' (I can't explain this - if you can you should give a lot more credence to this answer).
'high'+'born'='HIGHBORN'
Can you help me to learn more?
(Other definitions for highborn that I've seen before include "Of noble family, sounds lofty" , "Of aristocratic lineage" .)