往日
wǎng rì · HSK 7
day
📅 往 (past/gone-by) + 日 (day) = days gone by, former times
往 means past or gone-by, and 日 is day or sun. Stack them and you get the days that have already gone — former days, the old times.
往 — 彳 (step radical) + 主 (phonetic)
往 originally depicted a foot moving toward a place, with the 彳 radical signaling motion or walking. The right component 主 served mainly as a phonetic clue. Over time the meaning settled into 'to go (toward)' and, by extension, 'past' or 'previously'.
日 — pictograph of the sun
日 is a pictograph of the sun, originally drawn as a circle with a dot or stroke inside representing the sun's substance. Over time the round shape was squared off into the modern rectangular form. It means 'sun' and by extension 'day'.