Leaving street drive from end to end (4)

I believe the answer is:

thru

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'end' is the definition.
Both the definition and answer are adjectives.
Perhaps you can see an association between them that I can't see?

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

Can you help me to learn more?

(Other definitions for thru that I've seen before include "drive, avoiding street" , "Until the end of (US)" .)

I've seen this clue in The Sunday Times and The Times.

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