Whenever someone leaves something into the custody of another, usually but not necessarily against a fee, the contract between the two parties is said to be a deposit and that something must be surrendered on demand. The custodian cannot use the thing delivered or, if goods are fungible, must at all times keep the same quantity of the good under custody. When someting is delivered for another to use, usually but not necessarly against a fee, then the contract arising is called a loan. The loan is not callable on demand but has an agreed term for the delivery of the thing lended.
Regardless of definitions, whenever someone makes a bank deposit, it is actualy lending that money to the bank. He may feel this is unfair or incorrectly so. But it is unwise to treat the matter differently.