川下

1. Origins, structure, and basic meaning

• Structure: 川下 (かわしも) means downstream in the direction a river flows. It appears as direct movement direction and as the target of an orientation phrase.
• Basic usage: A dropped hat floats 川下へ; a person walks 川下に向かって.

2. Common pitfalls and similar expressions

• Object carried downstream and person walking toward lower reaches
  • へ marks the hat's actual movement; に向かって marks the walker's orientation. The reference is river flow, not low terrain generally.