Regret returning with sailors to get this train (8)

I believe the answer is:

eurostar

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'this train' is the definition.
(I've seen this before)

I can't explain the remainder of the clue.

(Other definitions for eurostar that I've seen before include "Chunnel service" , "International traveller" , "High-speed rail link between the UK and France" , "International train" , "Service from St Pancras" .)

I've seen this clue in The Times.

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