Pole tires alongside Welsh runner

I believe the answer is:

flagstaff

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'pole' is the definition.
(thesaurus)

'tires alongside welsh runner' is the wordplay.
'tires alongside' becomes 'flags' (I can't explain this - if you can you should believe this answer much more).
'welsh runner' becomes 'taff' (Welsh river, so something that 'runs').
'flags'+'taff'='FLAGSTAFF'

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(Other definitions for flagstaff that I've seen before include "Jack may be seen here" , "Pole for the standard" , "Arizona community" , "Ceremonial pole" , "somewhere in Arizona" .)

I've seen this clue in The Telegraph.

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