Insensitive, moving pearl out in the shade (9)

I believe the answer is:

penumbral

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'in the shade' is the definition.
I can't tell whether this definition defines the answer.

'insensitive moving pearl out' is the wordplay.
'insensitive' becomes 'numb' (synonyms).
'moving' is an anagram indicator.
'out' means one lot of letters goes inside another.
'pearl' is an anagram of 'peral'.
'numb' put within 'peral' is 'PENUMBRAL'.

Can you help me to learn more?

(Other definitions for penumbral that I've seen before include "Shadowy" , "of shadows" .)

I've seen this clue in The Daily Express.

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