The term 'SECURITIES EXPERT' can be broken down into two crossword solutions: BROKER (6 letters). A BROKER is a person or firm that acts as an intermediary between buyers and sellers. They are responsible for executing buy and sell orders for securities such as stocks, bonds, mutual funds, and other financial instruments. Brokers also provide advice to their clients on investments and other financial matters. They typically work in the financial services industry and must be licensed by the relevant regulatory body.