Only a ‘heap’, but it can be driven (4)

I believe the answer is:

pile

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'be driven' is the definition.
The definition and answer can be both to do with motion as well as being verbs in their base form.
Maybe they are linked in a way I don't understand?

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

Can you help me to learn more?

(Other definitions for pile that I've seen before include "large building" , "Nap of a carpet" , "supporting column" , "Post" , "Arrange in stacks" .)

I've seen this clue in the Evening Standard.

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