Careful, Kelvin insists during climb (4-6)

I believe the answer is:

risk-averse

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'careful' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'kelvin insists during climb' is the wordplay.
'kelvin' becomes 'K' (abbreviation for the unit of temperature).
'insists' becomes 'avers' (I've seen this in another clue).
'during' is an insertion indicator.
'climb' becomes 'rise' (synonyms).
'k'+'avers'='kavers'
'kavers' put inside 'rise' is 'RISK-AVERSE'.

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