One way remaining (4)

I believe the answer is:

left

I believe this is a double definition.

'one way' is the first definition.
(left or right)

'remaining' is the second definition.
(synonyms)

(Other definitions for left that I've seen before include "Sailed from" , "Allowed to remain" , "The side of socialism" , "Vacated; political wing" , "Socialist direction" .)

I've seen this clue in The Telegraph.

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