Always severe but not superficial (4)

I believe the answer is:

ever

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'always' is the definition.
(synonyms)

'severe but not superficial' is the wordplay.
'EVER' is hidden within the letters.
But, I am not sure how the hidden word is indicated.

Can you help me to learn more?

(Other definitions for ever that I've seen before include "In perpetuity" , "To the end of time" , "Always and permanent" , "At all times, always" , "Continuously" .)

I've seen this clue in the Sydney Morning Herald.

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