Permanently lying under transition (10)

I believe the answer is:

enduringly

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'permanently' is the definition.
(thesaurus)

'lying under transition' is the wordplay.
'lying under' can be anagrammed to 'ENDURINGLY'.
Though, I'm not sure how the anagram is indicated.

Can you help me to learn more?

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

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