Crossword Genius

Heartlessness and senselessness about olfactory offensiveness (10)

Ross

I believe the answer is:

inhumanity

'heartlessness' is the definition.

'senselessness about olfactory offensiveness' is the wordplay.
'senselessness' becomes 'inanity' ('inanity' can be a synonym of 'senselessness').
'about' means one lot of letters goes inside another.
'olfactory offensiveness' becomes 'hum' (hum is a bad smell).
'inanity' going around 'hum' is 'INHUMANITY'.

'and' is the link.

(Another definition for inhumanity that I've seen is " Cruelness, brutality".)

I've seen this clue in The Guardian.
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