When a street or area is in bad shape and poorer people live there, people with more money may start to move in. They buy the old houses, fix them, open nicer cafés and shops, and the place begins to look “better.” That slow change is to gentrify an area. Though actually, the word is not only about paint and new shops. Rents and house prices usually go up, so the families who lived there first often cannot stay. News writers, city planners, and neighbours who are hurt by this use gentrify with a sharp edge: it names the pushing-out, not just the cleaning-up. People who sell houses sometimes use it more loosely, almost as praise — “the area is being gentrified” meaning it is becoming fashionable. Listen for the speaker’s feeling; the same word can cheer or accuse.

仕紳化（台灣用語；中國大陸較常說「紳士化」）