hinder

1. Origins, structure, and basic meaning

• Structure: 妨 means hindering; its kun-reading is さまたげる and its on-reading is ぼう.
• Basic usage: 妨げる(さまたげる) means to obstruct or block, while 妨害(ぼうがい) means interference or obstruction.

2. Common pitfalls and similar expressions

• Blocking a flow and causing interference
  • 川の流れを妨げる means blocking a river's flow. 妨げる applies to a physical obstruction as well as to noise interrupting conversation.
  • 授業の妨害になった means that something disrupted the class. Since noise can be the source of interference, 妨害 is not restricted to a person's deliberate actions.