炎上

1. Origins, structure, and basic meaning

• Structure: 炎上(えんじょう) means burning fiercely and forms a verb with 炎上する.
• Basic usage: Alongside actual fires, it figuratively describes a surge of intense criticism online.

2. Common pitfalls and similar expressions

• 炎上 and 延焼
  • 炎上 focuses on something going up in flames; 延焼(えんしょう) focuses on fire spreading elsewhere. The warehouse example distinguishes the burning building from efforts to prevent the fire spreading around it.
• Where the criticism occurs
  • で in ネットで炎上する marks the setting of the criticism. The advertisement example goes on to describe its withdrawal following that criticism.