A train driver (8)

I believe the answer is:

muleteer

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This clue could be a double definition.

'a train' is the first definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.

'driver' is the second definition.
(thesaurus)

Can you help me to learn more?

(Other definitions for muleteer that I've seen before include "Animal driver" , "One driving obstinate animal" , "Driver of pack animals" .)

I've seen this clue in The Globe and Mail.

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