Sound virtuous (4)

I believe the answer is:

good

This clue is a double definition.

'sound' is the first definition.
('good' can be a synonym of 'sound')

'virtuous' is the second definition.
(I've seen this before)

(Other definitions for good that I've seen before include "Well-behaved, kind, or virtuous" , "Well done! Health-giving" , "benefit" , "Fine" , "(Of child) well-behaved" .)

I've seen this clue in The Independent.

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