牙城

1. Origins, structure, and basic meaning

• Structure: Written 牙城 and read がじょう, it literally suggests a fortified stronghold and figuratively a base firmly controlled by a group.
• Basic usage: It applies to a team's long-held domain and a region dominated by conservative support.

2. Common pitfalls and similar expressions

• Often a power base, not a fortress
  • Modern use commonly refers to a secure political, organizational, or competitive base.