Vacuum clearing house throughout (4)

I believe the answer is:

over

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'throughout' is the definition.
(I've seen this in other clues)

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

Can you help me to learn more?

(Other definitions for over that I've seen before include "Finished like cricket period" , "Six consecutive bowls in cricket" , "Past, surplus" , "Finished-up -left" , "Work out of hours" .)

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

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