noun
Public housing provided by a city or municipality, often for low-income residents.
彼は市営住宅に住んでいる。
He lives in municipal housing.
公営住宅 is a broader term for public housing run by any public entity (prefectural, municipal, etc.), while 市営住宅 specifically refers to housing operated by a city.
Compound of 市営 (municipal) and 住宅 (housing).