Enter into an arrangement with shrink (8)
I believe the answer is:
contract
'shrink' is the definition.
(I know that shrink can be written as contract)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for contract that I've seen before include "Shrink in written agreement" , "bargain" , "settlement" , "Covenant" , "Arrangement to commit murder" .)