Crossword Genius

Contractor stores one key grape (10)

Ross

I believe the answer is:

muscadelle

'grape' is the definition.
(type of grape)

'contractor stores one key' is the wordplay.
'contractor' becomes 'muscle' (I've seen this before).
'stores' indicates putting letters inside.
'one' becomes 'a'.
'key' becomes 'del' (del key on a keyboard).
'a'+'del'='adel'
'muscle' enclosing 'adel' is 'MUSCADELLE'.

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