Prepacked food or other goods have already been wrapped or put in a packet before they are sent to the shop. You buy them in their wrapping; the shop did not weigh them out for you from a big box. In British supermarket English this is a very ordinary word: prepacked cheese, prepacked salad, prepacked screws. It is not only food. Close to prepackaged, though prepackaged more often means the food is also ready to eat or only needs heating. Prepacked can just mean already in a packet. Though actually, shops and labels mix the two, and many speakers treat them as the same. Prepacked is more British; American English more often says prepackaged or just packaged.

預先包裝好的（英式超市用語；麵粉、螺絲也可能，不一定能直接吃）