鬱積

1. Origins, structure, and basic meaning

• Structure: 鬱積, read うっせき, denotes the long accumulation of grievances, thoughts, or feelings that have not been released.
• Basic usage: It describes long-pent-up grievances erupting at a meeting and accumulated thoughts released into a diary.

2. Common pitfalls and similar expressions

• Feelings building up internally
  • It is a build-up of grievances or thoughts held inside over time, rather than a momentary emotion.