reef

1. Origins, structure, and basic meaning

• Structure: 礁 has 17 strokes and concerns reefs below or near the surface of the sea.
• Basic usage: 暗礁 is read あんしょう, and 珊瑚礁 is read さんごしょう.

2. Common pitfalls and similar expressions

• Reefs and a figurative obstacle
  • 海面下の暗礁 means a reef below the sea surface.
  • 交渉は暗礁に乗り上げた figuratively means negotiations hit a stumbling block.
  • 珊瑚礁 means a coral reef.