Some trouble as extending contract (5)

I believe the answer is:

lease

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'contract' is the definition.
(I know that lease is a type of contract)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for lease that I've seen before include "Property rental agreement" , "Tenancy agreement" , "Contract for, say, use of building" , "Term of a rental contract" , "Let; rent" .)

I've seen this clue in The Sun.

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