Dash back after king left ridge (5)

I believe the answer is:

knurl

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'ridge' is the definition.
(thesaurus)

'dash back after king left' is the wordplay.
'dash back' becomes 'nur' (I can't justify this - if you can you should believe this answer much more).
'after' is a charade indicator (letters next to each other).
'king' becomes 'k'.
'left' becomes 'l' (common abbreviation).
'nur' put after 'k' is 'knur'.
'knur'+'l'='KNURL'

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(Other definitions for knurl that I've seen before include "Milled ridge (eg, on a screw-head)" , "Knot in wood" .)

I've seen this clue in The Telegraph.

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