1A large retail store that sells a wide variety of goods (clothing, food, household items, etc.) across multiple floors. Short for 'デパートメントストア' (department store).
デパートの一階には化粧品コーナーがある。
There's a cosmetics section on the first floor of the department store.
年末のデパートはお歳暮を買う人でにぎわう。
At year-end, department stores are crowded with people buying year-end gifts.
彼女はデパートの婦人服売り場で働いている。
She works in the women's clothing section of a department store.
2Listed in dictionaries as short for 'デパートメント' (department, as in a division), but in modern Japanese 'デパート' alone is essentially never used with this meaning — it is used exclusively to mean 'department store'.