Duck's grim smell (5)

I believe the answer is:

odour

'smell' is the definition.
('odour' can be a synonym of 'smell')

'duck's grim' is the wordplay.
'duck' becomes 'o'.
'grim' becomes 'dour' ('dour' can be a synonym of 'grim').
'o'+'dour'='ODOUR'

(Other definitions for odour that I've seen before include "Stink" , "Pong" , "A smell, good or bad" , "Regard" , "Any property detected by the olfactory system" .)

I've seen this clue in The Guardian and The Telegraph.

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