Cork train calling at all stations? (7)

I believe the answer is:

stopper

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'cork' is the definition.
(a cork stops a bottle)

I don't understand the rest of the clue.

(Other definitions for stopper that I've seen before include "One who checks" , "Maybe cork" , "Cork - goalkeeper?" , "Plug for a bottle" , "Perhaps cork" .)

I've seen this clue in The Telegraph.

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