Smell article relating to a person (5)
I believe the answer is:
human
'relating to a person' is the definition.
(relating to a human or humanity)
'smell article' is the wordplay.
'smell' becomes 'hum' (something with a bad smell is 'humming').
'article' becomes 'an' (indefinite article).
'hum'+'an'='HUMAN'
(Other definitions for human that I've seen before include "Relating to people" , "Of the species of homo sapiens" , "Relating to mankind" , "Being that's apt to err?" , "Man, woman or child" .)