Careful, Kelvin insists during climb (4-6)

'careful' is the definition.
I know nothing about this answer so I cannot judge 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' means one lot of letters goes inside another.
'climb' becomes 'rise' (synonyms).
'k'+'avers'='kavers'
'kavers' inserted within 'rise' is 'RISK-AVERSE'.

Can you help me to learn more?