Part of body has nasty smell, not totally healthy (5)
I believe the answer is:
bowel
'part of body' is the definition.
('bowel' is part of 'body')
'nasty smell not totally healthy' is the wordplay.
'nasty smell' becomes 'bo' (body odour).
'not totally' means to remove the last letter.
'healthy' becomes 'well' ('well' can be similar in meaning to 'healthy').
'well' with its last letter taken off is 'wel'.
'bo'+'wel'='BOWEL'
'has' is the link.
(Other definitions for bowel that I've seen before include "Gut" , "Large intestine" , "part of canal" .)