暦

1. Origins, structure, and basic meaning

• Structure: 暦 is read as こよみ and means “calendar” and “calendar system”.
• Basic usage: It refers to a calendar used for scheduling and an old calendrical system studied in an exhibit.

2. Common pitfalls and similar expressions

• 暦に予定を書く / 暦の仕組み
  • 暦に予定を書く refers to a physical calendar, while 暦の仕組み means the calendrical system.