Money held in trust (6)
I believe the answer is:
escrow
'money held in trust' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for escrow that I've seen before include "It's held in trust or as a security" , "Conditional deed held by third party" , "Something held until a condition is fulfilled" , "back-up security" , "Deed or deposit held until a condition is fulfilled" .)