underpopulated area; depopulated region
Refers to a region with a declining or very low population, often used in discussions of rural decline and regional policy.
In underpopulated areas, maintaining public transportation is difficult.
The government is working on revitalizing depopulated regions.
過疎 is the abstract concept of depopulation, while 過疎地域 specifically refers to an area affected by it.
Antonym: an overcrowded or densely populated area.
Compound of 過疎 (depopulation) and 地域 (area, region). 過疎 itself is composed of 過 (exceed, too much) and 疎 (sparse, neglect).