Arrow hound? (7)
I believe the answer is:
pointer
I believe this clue is a double definition.
'arrow' is the first definition.
(I know that arrow can be written as pointer)
'hound?' is the second definition.
(thesaurus)
(Other definitions for pointer that I've seen before include "Hint (for a dog?)" , "stick used for instruction?" , "under control of mouse" , "Tip; dog" , "Dog; cursor" .)