陰謀

1. Origins, structure, and basic meaning

• Structure: 陰謀（いんぼう） means a secret plan to harm others or achieve an improper aim.
• Basic usage: It refers to a concealed harmful plan, such as the plot threatening the kingdom in the novel.

2. Common pitfalls and similar expressions

• A secret versus a plot
  • 秘密 means information that is not known, while 陰謀 specifically involves a secretly devised harmful plan.
• Its relation to a rumor
  • The second example warns against linking 根拠のない噂 to a conspiracy.