Transport direct (5)

I believe the answer is:

train

I believe this is a double definition.

'transport' is the first definition.
(I know that train is a type of public transport)

'direct' is the second definition.
(I know that direct can be written as train)

(Other definitions for train that I've seen before include "Number of animals moving in a line, like camels" , "Following" , "Teach (person) a skill" , "Instruct - exercise" , "Exercise in preparation for some event" .)

I've seen this clue in the Evening Standard.

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