Determination not to be intestate? (4)

I believe the answer is:

will

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'determination' is the definition.
(will can mean determination or desire)

I don't understand the rest of the clue.

(Other definitions for will that I've seen before include "Intention; legal document" , "Shakespeare < 's intention to leave something" , "Determination; 22 author" , "Fixed intention" , "Record of final wishes and testament" .)

I've seen this clue in the Evening Standard.

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