It is a place where shares of pubic listed companies are traded. A stock market, equity market or share market is the aggregation of buyers and sellers of stocks, which
represent ownership claims on businesses; these may include securities listed on a public stock exchange as well as those only traded privately.
The stock market is a general term which is related to a place where stocks are traded. A stock exchange is more specific to the place where the trading is executed, such as BSE, NSE, NYSE, NASDAQ and so on. If you say you trade in the stock market it would mean that you buy and sell shares/equity.