降雨

1. Origins, structure, and basic meaning

• Structure: 降雨 (こうう) combines falling 降 and rain 雨 to denote the occurrence of rainfall.
• Basic usage: It is used for rain affecting the ground or being measured over a period.

2. Common pitfalls and similar expressions

• Rainfall versus its measured amount
  • 降雨 is the event or presence of rain, whereas 降雨量 specifically names the quantity measured.