This is the 1944th most frequent Korean word.
대형마트
Large discount store.
Here, '대형마트' is used to specify the location - the large supermarket - where the action of grocery shopping took place.
대형마트에서 장을 봤어요.
I went grocery shopping at the big supermarket.
In this sentence, '대형마트' refers to a type of store, emphasizing the prevalence of such stores in Korea.
한국에는 대형마트가 많습니다.
In Korea, there are many large supermarkets.
The term '대형마트' is used to highlight the place of opportunity to buy various items.