Smell an earthling (5)

I believe the answer is:

human

'earthling' is the definition.
(thesaurus)

'smell an' is the wordplay.
'smell' becomes 'hum' (I have seen 'Unpleasant smell ' mean 'hum' so perhaps 'smell' could also mean 'hum').
'hum'+'an'='HUMAN'

(Other definitions for human that I've seen before include "Relating to mankind" , "Of the species of homo sapiens" , "Relating to a person" , "Relating to people" , "Man, woman or child" .)

I've seen this clue in The Times.

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