Greet criminal during depression as laundering agent (9)
I believe the answer is:
detergent
'agent' is the definition.
(detergent is a kind of agent)
'greet criminal during depression' is the wordplay.
'criminal' indicates an anagram.
'during' means one lot of letters goes inside another.
'depression' becomes 'dent' (dent is a kind of depression).
'greet' with letters rearranged gives 'terge'.
'terge' inserted within 'dent' is 'DETERGENT'.
'as laundering' acts as a link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for detergent that I've seen before include "Soluble cleanser" , "Synthetic cleaning substance for washing machines" , "Cleansing substance used for washing clothes" , "Soluble cleansing agent" , "Cleansing solvent" .)