A large stream in the garden (4)

I believe the answer is:

eden

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'garden' is the definition.
(I know that Eden is a garden)

I cannot understand how the rest of the clue works.

(Other definitions for eden that I've seen before include "at Number Ten once?" , "The primal garden" , "Paradisal garden" , "Biblical garden" , "The near-perfect garden" .)

I've seen this clue in the Evening Standard.

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