A hollow "Hard times for everybody" (10)

I believe the answer is:

depression

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'a hollow' is the definition.
(thesaurus)

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

(Other definitions for depression that I've seen before include "Blues" , "Nineteen twenty nine financial slump" , "gloom" , "mental anguish" , "Pit" .)

I've seen this clue in the Evening Standard.

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