Crossword Genius

Very rainy start to week quickly disheartened everyone (9)

Ross

I believe the answer is:

monsoonal

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'very rainy start to week' is the definition.
I can't tell whether this defines the answer.

'quickly disheartened everyone' is the wordplay.
'quickly' becomes 'monsoon' (I can't justify this - if you can you should believe this answer much more).
'disheartened' means to remove the middle letters (the middle or heart is removed).
'everyone' becomes 'all' (all people).
'all' with its centre removed is 'al'.
'monsoon'+'al'='MONSOONAL'

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