忌まわしい

1. Origins, structure, and basic meaning

• Structure: 忌まわしい is read いまわしい. It describes something abhorrent, repellent, or ominous.
• Basic usage: It modifies a memory the protagonist wants to shake off and a mask regarded as ominous.

2. Common pitfalls and similar expressions

• Modifying a memory
  • 忌まわしい記憶 is a memory abhorrent enough that the protagonist wants to shake it off.
• Regarded as ominous
  • In 忌まわしい物として封印した, the mask is sealed away because it is regarded as ominous.