白菜
bái cài · HSK 3
pak choi
🥬 白 (white) + 菜 (vegetable) = white vegetable = Chinese cabbage
The compound literally reads 'white vegetable' — named for the pale white stalks of napa/pak choi. 菜 is the general word for vegetable or dish, so 白菜 slots into a whole family of named-by-color or named-by-shape veggies.
白 — pictograph; resembles 日 (sun) with a stroke on top
白 is generally considered a pictograph, traditionally explained as depicting the sun rising with a ray of light above it, hence the meaning 'white' or 'bright.' Some scholars instead see it as a drawing of a thumbnail or an acorn. From 'bright' it extended to 'clear,' 'plain,' and 'to state plainly.'
菜 — grass radical 艹 + 采 (pick)
菜 combines the grass radical 艹 (plants) with 采, which depicts a hand picking fruit from a tree and also supplies the sound. Originally meaning edible plants one gathers, it came to mean vegetables, and by extension any dish or cuisine.