Refers to a circular shape or loop, often in abstract, mathematical, or literary contexts. More formal than 輪 (わ) or 丸 (まる).
This story has a circular structure.
Find the area of the circle in mathematics.
solid torus
torus; anchor ring
Compound of 円 (えん, 'circle') and 環 (かん, 'ring'). Both kanji carry similar meanings, reinforcing the idea of a circular form.