Plonker dismissing new upper-class language (4)

I believe the answer is:

urdu

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'language' is the definition.
(Urdu is an example)

I don't understand the remainder of the clue.

(Other definitions for urdu that I've seen before include "Sanskrit language" , "Analyse and develop (an idea) in detail" , "Channel to north of Isle of Wight" , "Language akin to Hindi" , "Official language used in Pakistan" .)

I've seen this clue in The Sunday Times and The Times.

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