Ruled the stray dog should never run loose in it (8)
I believe the answer is:
governed
'ruled' is the definition.
('govern' can be a synonym of 'rule')
'stray dog should never run loose in it' is the wordplay.
I cannot quite see how this works, but
an anagram of 'never' is 'verne' which is within the answer.
an anagram of 'dog' is 'god' which is present in the remaining letters.
No letters remain.
This explanation may well be incorrect...
'the' is the link.
Can you help me to learn more?
(Other definitions for governed that I've seen before include "Exercised authority over" , "Ruled" , "kept under control" .)