Offensive, unfeeling, lousy, heartless (4)

I believe the answer is:

ugly

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'offensive' is the definition.
(synonyms)

'unfeeling lousy heartless' is the wordplay.
'unfeeling' becomes 'ug' (I can't justify this - if you can you should believe this answer much more).
'heartless' means to remove the middle letters.
'lousy' with its centre taken out is 'ly'.
'ug'+'ly'='UGLY'

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(Other definitions for ugly that I've seen before include "Deficient in beauty" , "Far from beautiful" , "Lacking in beauty" , "Threatening; nasty" , "Unlovely" .)

I've seen this clue in The Independent.

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