邸宅

ていたく · teitaku · JLPT N1 · noun

sign of the zodiac

🏡 邸 (estate) + 宅 (house) = a house on an estate, i.e. a mansion

邸 is the grand-estate character, as in 官邸 (official residence). 宅 is plain home, as in 自宅 (one's own home). Stack them and you get a big home.