Low voice, alien for hound (6)
I believe the answer is:
basset
'hound' is the definition.
(basset hound is an example)
'low voice alien' is the wordplay.
'low voice' becomes 'bass' (I've seen this before).
'alien' becomes 'et' (extra terrestrial).
'bass'+'et'='BASSET'
'for' is the link.
(Other definitions for basset that I've seen before include "GAME" , "Smooth-haired, long-eared hound" , "Low-set hound" , "Short-legged dog" , "Hound (named Fred?)" .)