Enlightenment derived from safe oregano (3,2,6)

I believe the answer is:

age of reason

'enlightenment' is the definition.
(synonyms)

'derived from safe oregano' is the wordplay.
'derived from' indicates anagramming the letters.
'safe'+'oregano'='safeoregano'
'safeoregano' is an anagram of 'AGE OF REASON'.

(Another definition for age of reason that I've seen is " "Enlightenment"".)

I've seen this clue in The Daily Express.

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