Cold in the extreme? Cold and peaky in the extreme! (9)

I believe the answer is:

chilliest

'cold in the extreme?' is the definition.
(extremely chilly)

'cold and peaky in the extreme' is the wordplay.
'cold' becomes 'c' (eg on taps).
'and' says to put letters next to each other.
'peaky in the extreme' becomes 'hilliest' (having lots of peaks or hills).
'c'+'hilliest'='CHILLIEST'

I've seen this clue in The Independent.

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