A person or firm into whose name securities or other properties are transferred in order to facilitate transactions, while leaving the customer as the actual owner.
Investopedia explains 'Nominee' A "nominee account" is a type of account in which a stockbroker holds shares belonging to clients, making buying and selling those shares easier. In such an arrangement shares are said to be held in street name.
Street Name When securities are held in the name of a broker or other nominee, as opposed to holding them in the customer's name.