Fitting top outwardly most vivid (9)

I believe the answer is:

brightest

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'fitting top outwardly most vivid' is the definition.
I can't tell whether this defines the answer.

'fitting top outwardly most vivid' is the wordplay.
'fitting top' becomes 'best' (similar in meaning. I am not sure about the 'fitting' bit.).
'outwardly' is an insertion indicator (some letters go on the outside).
'most' means to remove the first letter.
'vivid' becomes 'bright' (synonyms).
'bright' with its initial letter taken away is 'right'.
'best' enclosing 'right' is 'BRIGHTEST'.

Can you help me to learn more?

(Another definition for brightest that I've seen is " Most intelligent".)

I've seen this clue in The Daily Express.

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