1. A stock exchange.

2. The market in which stocks are bought and sold, usually including the organized exchanges and over-the-counter markets in a particular country or economic region: the US stock market.

3. The buyers and sellers of stocks: The stock market was jittery all morning.

4. The business transacted in such a market: The stock market has been sluggish.

5. The price or value of the stocks trading in a market: a rising stock market.