Despicable rise in attention about national costume (7)

I believe the answer is:

ratlike

'despicable' is the definition.
(contemptible like a rat)

'rise in attention about national costume' is the wordplay.
'rise in' is a reversal indicator.
'attention' becomes 'ear' (having someone's ear is having their attention).
'about' means one lot of letters goes inside another.
'national costume' becomes 'kilt' (national costume of Scotland).
'ear' enclosing 'kilt' is 'ekiltar'.
'ekiltar' written backwards gives 'RATLIKE'.

I've seen this clue in The Guardian.

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