A loro account is an account that one bank holds with another bank, when a third bank is talking about it. The word is Italian for "theirs". It is not a different kind of account: the same deposit is a nostro to the bank that owns it and a vostro to the bank that keeps it. All three labels are compared in Nostro vs Vostro vs Loro Accounts.
For example, if Bank A in London holds US dollars at Bank B in New York, Bank A calls it its nostro, Bank B calls it a vostro, and Bank C, which asks Bank B to credit that account for a payment, calls it a loro account. The term appears in correspondent banking and in payment instructions where a bank must name the exact account to debit or credit. It is used much less often than nostro and vostro.