行家
háng jiā · HSK 7
expert
🎓 行 (háng = trade/line of work) + 家 (specialist) = a specialist in the trade, an expert
Here 行 is read háng meaning a trade or line of business, not xíng (to walk). Add 家, the suffix for a specialist (as in 专家 expert, 画家 painter), and 行家 is the seasoned insider who knows the trade cold.
行 — crossroads pictograph (left 彳 + right 亍)
行 originally pictured a four-way crossroads in oracle bone script, with two paths meeting. From 'road' it extended to 'walk, go, travel,' and then to 'a row, line' or 'business firm' (read háng). The two halves 彳 and 亍 are the split sides of that ancient crossroads.
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').