木曜日
もくようび · mokuyoubi · JLPT N5 · noun
Thursday
🌳 木曜日 = wood/tree (木) + day of the week (曜日): tree day
Japanese weekdays follow the planets, like European ones. 木星 (wood star) is Jupiter, and Thursday is Jupiter's day: jeudi in French, jueves in Spanish. So moku (wood) + youbi (weekday) lines up with Thursday.
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'.