A prefecture is a large area of a country that has its own local government — not the national government in the capital, but a government for that area. You meet the word most often with Japan, which is divided into 47 prefectures. English uses this one word for all of them, though actually Japanese does not: 都, 道, 府 and 県 are different kinds of place, and a 県 is not quite the same as a 府. France has prefectures too: there the word can mean the area, or the office of the préfet, the official who represents the state. In older writing about China, 府 (and sometimes 郡, 縣 or 州) is also called a prefecture. It is a map-and-government word, a little formal. People do not use it for a neighbourhood, a school district, or Taiwan’s own 縣 — those 縣 are counties in English, even though the character matches Japan’s 県. The English label is a habit of translation, not a universal type of place.