Said it’s a surface charm (6)

I believe the answer is:

appeal

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'charm' is the definition.
(synonyms)

I cannot understand how the rest of the clue works.

(Other definitions for appeal that I've seen before include "Petition or attraction" , "A crustacean" , "Seek to have verdict overturned" , "Beg" , "Submit case to higher court for review" .)

I've seen this clue in the Evening Standard.

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