Obnoxious type of quiet Scottish island (6)

I believe the answer is:

shmuck

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'obnoxious type' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'quiet scottish island' is the wordplay.
'quiet' becomes 'sh' (both can be said to tell someone to be quiet).
'scottish island' becomes 'muck' (Muck is an island of the Small Isles).
'sh'+'muck'='SHMUCK'

'of' is the link.

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I've seen this clue in The Guardian.

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