Borrower
One who borrows. From lenders. Under loans. Involves indebtedness.
If one borrows by means of deposits, you ought to be a licensed deposit-taking institution, which is another way of saying a bank.
Being a swap counterparty is not to be a borrower, although one’s mark-to-market exposure, if not collateralised, can certainly resemble indebtedness even though, strictly speaking, it isn't.