noun
Refers to a ridge of rock, coral, or sand near the surface of the sea. Often used in compound words like 珊瑚礁 (coral reef) or 暗礁 (hidden reef).
船は暗礁に乗り上げた。
The ship ran aground on a hidden reef.
この海域には多くの珊瑚礁がある。
There are many coral reefs in this sea area.
岩礁 specifically means a rocky reef, while 礁 is a broader term that can include coral or sand reefs.
珊瑚礁 is a coral reef, a specific type of 礁.
The kanji 礁 is composed of 石 (stone) and 焦 (scorch/focus), suggesting a stone formation that is visible or dangerous. The reading しょう is the on'yomi.