contract

a legal document that states and explains a formal agreement between two different people or groups, or the agreement itself:

a contract of employment / a temporary/building contract

They could take legal action against you if you break (the terms of) the contract.

My solicitor is drawing up (= writing) a contract.

They're the firm of architects who won the contract to design the Museum of Fine Art extension.

They will only agree to sign the contract if certain conditions are met.

to make or become shorter or narrower or generally smaller in size / to become smaller in amount or quantity:

In spoken English, "do not" often contracts to "don't".

As it cooled, the metal contracted.

A recession is a period when the economy is contracting.

Agricultural output has contracted by 2.3 percent.

When wet fibers dry, they contract.

to catch or become ill with a disease:

He contracted malaria while he was travelling.

She contracted pneumonia and was hospitalized.