Guess about 550, dolefully (5)

I believe the answer is:

sadly

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'dolefully' is the definition.
Both the answer and definition are adverbs. Perhaps they are linked in a way I don't understand?

I don't understand the remainder of the clue.

Can you help me to learn more?

(Other definitions for sadly that I've seen before include "Mournfully" , "Alas" , "Lamentably, unfortunately" , "I regret to say" , "With sorrow" .)

I've seen this clue in the Evening Standard.

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