Crossword Genius

Sadly in arrears, a labourer's given up (4)

Ross

I believe the answer is:

alas

'sadly' is the definition.
('alas' is used to express regret)

'in arrears a labourer's given up' is the wordplay.
'in' indicates a hidden word.
'given up' says the letters should be written in reverse (in a down clue, letters go up).
'sala' is hidden within 'arrears a labourers'.
'sala' backwards is 'ALAS'.

(Other definitions for alas that I've seen before include "Expression of grief or misfortune" , "Regrettably, unfortunately" , "Regretfully!" , "By bad luck" , "Proper, respectable" .)

I've seen this clue in The Telegraph.
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