家内
かない · kanai · JLPT N4 · noun
wife
🏠 家内 = house + inside: the one inside my house, my own wife
家 (ka, house) + 内 (nai, inside). A humble term a husband uses for his own wife, never for someone else's. Sound hook: kanai is like can I? as in can I check with my wife first.
家 — roof 宀 + pig 豕
Originally a pictograph of a pig under a roof, since domesticated pigs were kept in or under the home in ancient China. Over time the meaning broadened from 'household' to 'family,' and by extension 'home' or a specialist (as in 专家, 'expert').
内 — enclosure 冂 + enter 入
内 originally depicted something entering (入) into an enclosed space (冂), giving the core sense of 'inside' or 'within'. The pictographic image of going into a covered area extended naturally to meanings like inner, internal, and inland. It contrasts with 外 ('outside').