Horse son walked randomly round centre of stables (8)
I believe the answer is:
skewbald
'horse' is the definition.
(I've seen this before)
'son walked randomly round centre of stables' is the wordplay.
'son' becomes 's' (genealogical abbreviation for son).
'randomly' is an anagram indicator (I've seen 'roaming randomly' mean this).
'round' is an insertion indicator.
'centre of' says to take the centre.
The middle of 'stables' is 'b'.
's'+'walked'='swalked'
'swalked' is an anagram of 'skewald'.
'skewald' going around 'b' is 'SKEWBALD'.
(Other definitions for skewbald that I've seen before include "Horse with patches of white and another colour" , "Marked with patches of white and a colour" , "maybe brown and white" , "(Horse) with white and coloured marks" , "patchy" .)