convenience store

mini-market, small grocery store

A convenience store is a small store or shop. They are often located alongside busy roads, or at gas/petrol stations. This can take the form of gas stations supplementing their income with retail outlets, or convenience stores adding gas to the list of goods that they offer. Railway stations also often have convenience stores. They are also frequently located in densely-populated urban neighborhoods.
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a neighbourhood store which stocks frequently purchased items such as milk, bread and cigarettes.