Relents as out in vigilant state (9)

I believe the answer is:

alertness

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'vigilant state' is the definition.
'alertness' can be an answer for 'state' (alertness is a kind of state). I am not sure about the 'vigilant' bit.

'relents as out' is the wordplay.
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'relents'+'as'='relentsas'
'relentsas' anagrammed gives 'ALERTNESS'.

'in' acts as a link.

Can you help me to learn more?

(Other definitions for alertness that I've seen before include "It's needed to respond quickly to danger" , "State of vigilance and watchfulness" , "Wakeful characteristic" , "Showing attentive nature" , "Watchful attitude" .)

I've seen this clue in The Irish Times.

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