What some do with onion and melon ices, removing energy for super-chilling? (10)
I believe the answer is:
cryogenics
'super-chilling?' is the definition.
(science of freezing dead bodies)
'what some do with onion and melon ices removing energy' is the wordplay.
'what some do with onion' becomes 'cry' (chopping onions might make you cry).
'and' is a charade indicator (letters next to each other).
'melon' becomes 'ogen' (I've seen this before).
'removing' indicates named letters should be taken away.
'energy' becomes 'e' (physics symbol as in E=mc2).
'ices' with 'e' removed is 'ics'.
'cry'+'ogen'+'ics'='CRYOGENICS'
'for' acts as a link.
(Other definitions for cryogenics that I've seen before include "Science dealing with very low temperatures" , "Physics of very low temperatures" .)