蔚

Phono-semantic compound:

艸 (풀 초, “grass, plant”) — semantic, indicating plants/herbs.

尉 (벼슬 위, “official, commander”) — phonetic, providing the sound.

Thus, originally referring to lush vegetation or plants associated with the name “蔚”, later extended to place names and other meanings.

蔚山 (울산) — major city in Korea, literally “Mount Ul.”

蔚藍 (울람 / 위람) — azure, sky-blue.

蔚然 (위연) — luxuriant, flourishing.

蔚起 (위기) — to arise in great numbers, flourish.

In Korean usage, when used in toponyms, it is always read as 울 (e.g., 울산 蔚山).

When used in botanical terms (like 제비쑥, mugwort), both 울 and 위 are found.