Key argument in encryption system (6)
I believe the answer is:
escrow
'encryption system' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'key argument' is the wordplay.
'key' becomes 'esc' ('Escape' key on a computer keyboard).
'argument' becomes 'row' (to row is to argue).
'esc'+'row'='ESCROW'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for escrow that I've seen before include "It's held in trust or as a security" , "Legal deed to take effect when a condition is fulfilled" , "Conditional deed held by third party" , "Deed or deposit held until a condition is fulfilled" , "goods held by third party" .)