Sad, though loaded with unearned income? (7)

I believe the answer is:

doleful

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'sad' is the definition.
(I've seen this in another clue)

I don't understand how the remainder of the clue works.

(Other definitions for doleful that I've seen before include "down in the dumps" , "Mournful" , "Miserable" , "Sad-looking" , "Cheerless" .)

I've seen this clue in the Evening Standard.

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