Crossword Genius

Mutter in agitation about parking for orchestra member (7)

Ross

I believe the answer is:

trumpet

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'mutter' is the definition.
(thesaurus)

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(Other definitions for trumpet that I've seen before include "Brass wind instrument" , "Loudly sound - instrument" , "brassy type" , "Centre of daffodil flower" , "Orchestral or military instrument" .)

I've seen this clue in The Times.
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