More expensive relative to some measure of underlying value like earnings or book value. If you look at the P/E ratio (price-to-earnings) of a stock, a higher r

More expensive relative to some measure of underlying value like earnings or book value. If you look at the P/E ratio (price-to-earnings) of a stock, a higher ratio means you're paying more to buy enough stock to get $1 of earnings, which in a sense means that the stock is more expensive.