Criminal swore to keep many assets stashed away until terms are met (6)
I believe the answer is:
escrow
'assets stashed away until terms are met' is the definition.
I can't judge whether this definition defines the answer.
'criminal swore to keep many' is the wordplay.
'criminal' indicates anagramming the letters.
'to keep' means one lot of letters goes inside another.
'many' becomes 'c' (C is the Roman numeral for 100).
'swore' anagrammed gives 'esrow'.
'esrow' enclosing 'c' is 'ESCROW'.
Can you help me to learn more?
(Other definitions for escrow that I've seen before include "back-up security" , "Legal deed to take effect when a condition is fulfilled" , "It's held in trust or as a security" , "Deed held by third party effective when a condition is met" , "Conditional deed held by third party" .)