noun
three-family house; three-generation home
A single residential building designed to accommodate three separate family units, often for multigenerational living.
三世帯住宅を建てて、親と子と孫で一緒に住んでいます。
We built a three-family house and live together with our parents, children, and grandchildren.
Refers to a two-family house, while 三世帯住宅 is for three families.
Compound of 三 (san, 'three'), 世帯 (setai, 'household'), and 住宅 (jūtaku, 'residence').