超市 (chāoshì) is a noun meaning 'supermarket,' short for 超级市场. It refers to a large self-service retail store selling food and household goods. It is one of the most commonly used words for everyday shopping locations.
我下班后去超市买点菜。
wǒ xiàbān hòu qù chāoshì mǎi diǎn cài.
I'll go to the supermarket to buy some groceries after work.
这家超市的东西又便宜又新鲜。
zhè jiā chāoshì de dōngxi yòu piányi yòu xīnxiān.
The things at this supermarket are both cheap and fresh.
小区门口新开了一家超市。
xiǎoqū ménkǒu xīn kāi le yī jiā chāoshì.
A new supermarket just opened at the entrance of the residential complex.