Dog seen in Soho, undernourished (5)
I believe the answer is:
hound
'dog' is the definition.
(hound is a kind of dog)
'in soho undernourished' is the wordplay.
'in' indicates a hidden word.
'HOUND' is hidden within 'soho undernourished'.
'seen' acts as a link.
(Other definitions for hound that I've seen before include "Chase after" , "despicable creature" , "Harry" , "Give no peace" , "despicable person" .)