Stable against housing single horse (8)
I believe the answer is:
stallion
'horse' is the definition.
(I know that stallion is a type of horse)
'stable against housing single' is the wordplay.
'stable' becomes 'stall' (I've seen this in other clues).
'against' means one lot of letters go next to another.
'housing single' becomes 'ion' (I am not sure about this - if you are sure you should believe this answer much more).
'stall'+'ion'='STALLION'
Can you help me to learn more?
(Other definitions for stallion that I've seen before include "Male horse lost in atolls" , "Male horse, often used for breeding" , "Mount" , "Mare's mate" , "Male steed" .)