Opening left for sailors (4)

I believe the answer is:

port

I believe this is a double definition.

'opening' is the first definition.
(port is a kind of opening)

'left for sailors' is the second definition.
(term for the left of a ship)

(Other definitions for port that I've seen before include "Alcoholic drink after meal or sea shelter" , "Harbour; alcoholic drink" , "Stanley perhaps" , "Grimsby, perhaps" , "Wine left at sea ?" .)

I've seen this clue in The Times.

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