Smelling some atrocious niff in garden (8)

I believe the answer is:

sniffing

'smelling' is the definition.
(sniffing is a kind of smelling)

'some atrocious niff in garden' is the wordplay.
'some' indicates a hidden word (some parts of the word are used).
'SNIFFING' is hidden in the letters of 'atrocious niff in garden'.

(Other definitions for sniffing that I've seen before include "Inhaling audibly" , "Drawing air audibly up the nose" , "Inhaling sharply" .)

I've seen this clue in The Telegraph.

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