A word for something you give and the receiver knows you will come back to get it? [closed]
Collateral
(n) property (such as securities) pledged by a borrower to protect the interests of the lender
A security deposit.
https://www.investopedia.com/terms/s/security-deposit.asp
A security deposit for renting an apartment is returned if the apartment is in good condition when you vacate it.
A security deposit for renting a bike or a boat ensures that you’ll return the rented item to get the deposit back. Sometimes a credit card is used with the agreement that the card will be charged if you don’t return the item.