Crossword Genius

Bush and Biden primarily talk rubbish (7)

Ross

I believe the answer is:

bramble

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'bush' is the definition.
(thesaurus)

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(Other definitions for bramble that I've seen before include "Blackberry shrub" , "Wild thorny shrub" , "Thorny bush" , "Blackberry plant" , "berries" .)

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