火事

1. Origins, structure, and basic meaning

• Structure: 火事, read かじ, combines fire 火 with incident 事 to denote fire as an accident or disaster.
• Basic usage: It denotes a damaging fire that can spread through a building or area, as in 火事が起きる.

2. Common pitfalls and similar expressions

• Scope and context
  • Unlike controlled fire 火 used for cooking or heat, it is fire as an accident or disaster.