“Cold” without the “ol”? (9)

I believe the answer is:

heartless

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'the ol?' is the definition.
I can't tell whether this defines the answer.

'cold without' is the wordplay.
'cold' becomes 'heart' (I can't justify this - if you can you should give a lot more credence to this answer).
'without' becomes 'less'.
'heart'+'less'='HEARTLESS'

Can you help me to learn more?

(Other definitions for heartless that I've seen before include "Cruel and unfeeling" , "Uncaring" , "Lacking pity due to cardiac deficiency" , "hard?" , "Cold-blooded" .)

I've seen this clue in the Evening Standard.

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