Pumping centre (5)

I believe the answer is:

heart

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'centre' is the definition.
(I know that centre can be written as heart)

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

Can you help me to learn more?

(Other definitions for heart that I've seen before include "Muscular organ for blood circulation" , "one in suit" , "Earth (anag) -- compassion" , "It beats" , "Not a club" .)

I've seen this clue in the Evening Standard.

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