Base, base hound (7)
I believe the answer is:
bedevil
'hound' is the definition.
(thesaurus)
'base base' is the wordplay.
'base' becomes 'bed' (both can mean the bottom of something).
'base' becomes 'evil' (I've seen this in another clue).
'bed'+'evil'='BEDEVIL'
(Other definitions for bedevil that I've seen before include "Worry, harass" , "Cause continual difficulties" , "Afflict" , "Throw into confusion" , "Cause problems for" .)