淡水

1. Origins, structure, and basic meaning

• Structure: 淡水 is read as たんすい and is a noun for water with very little salt, contrasted with seawater.
• Basic usage: Saying that a fish lives in freshwater appears in 淡水に生息する, while contrasting freshwater with seawater appears in 淡水と海水の違い.

2. Common pitfalls and similar expressions

• Difference from 海水
  • 淡水 is the water type contrasted with saline seawater.