Disdainful second refusal over British blunder (8)

I believe the answer is:

snobbish

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'disdainful' is the definition.
(thesaurus)

'second refusal over british blunder' is the wordplay.
'second' becomes 's' (common abbreviation).
'refusal over' becomes 'no' (I can't justify this - if you can you should believe this answer much more).
'british' becomes 'b' (abbreviation e.g. in BBC).
'blunder' becomes 'bish' (I've seen this before).
's'+'no'+'b'+'bish'='SNOBBISH'

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(Other definitions for snobbish that I've seen before include "stuck up" , "Stuck-up" , "Given to overvaluing social status" , "Posh" , "Toffee-nosed" .)

I've seen this clue in The Times.

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