The highest bid to buy and the lowest offer to sell a security in a given market at a given time. If you ask your financial advisor for a “quote” on a stock, he or she may come back with something like “45 1/4 to 45 1/2.” This means that $45.25 is the highest price any buyer wanted to pay at the time the quote was given on the floor of the exchange and that $45.50 was the lowest price that any seller would take at the same time. (See: Bid and Asked)