境界

1. Origins, structure, and basic meaning

• Structure: 境界(きょうかい) means a boundary separating two areas.
• Basic usage: It is used both for a physical boundary between towns and for an abstract division between work and rest.

2. Common pitfalls and similar expressions

• A national border and broader boundaries
  • 国境(こっきょう) is a border between countries; 境界 applies to a wider range of areas.
• The homophone 教会
  • 教会 is also read きょうかい, but means a church. It is a different word from a dividing boundary.