noun
Geographical term for a river mouth where freshwater meets the sea, often triangular in shape.
三角江は、川が海に流れ込む場所に形成される。
An estuary is formed where a river flows into the sea.
Compound of 三角 (さんかく, 'triangle') and 江 (こう, 'inlet, bay'), referring to the triangular shape of an estuary.