Train drivers can take it to Washington (3)

I believe the answer is:

aim

'train' is the definition.
(synonyms)

I don't understand how the remainder of the clue works.

(Other definitions for aim that I've seen before include "Point (gun); intention" , "Direct, intend" , "Goal, objective" , "Point or direct, a weapon say" , "intent" .)

I've seen this clue in The Times.

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