noun
roundabout; traffic circle; rotary
A circular intersection where traffic flows around a central island. In Japan, this term is used in official traffic contexts, though physical roundabouts are less common than in some other countries.
See also: ロータリー
この町の環状交差点は、事故が減ったことで知られている。
The roundabout in this town is known for reducing accidents.
環状交差点では、右回りに進むのがルールです。
At a roundabout, the rule is to go clockwise.
ロータリー is a more common, everyday term for a traffic circle or rotary, while 環状交差点 is the formal, official term used in traffic regulations and engineering.
Compound of 環状 (kanjō, 'ring-shaped') + 交差点 (kōsaten, 'intersection'). A relatively modern term adopted in official traffic terminology.