習慣

1. Origins, structure, and basic meaning

• Structure: 習慣 is read as しゅうかん and is a noun for either a repeated personal habit or a custom maintained by a community.
• Basic usage: Use 散歩することが習慣だ for an individual routine and 地域には習慣がある for a local custom.

2. Common pitfalls and similar expressions

• Habit and custom
  • A grandfather’s morning walk is a personal habit, while celebrating spring with a fire festival is a community custom.
• Repetition rather than one event
  • Forms such as 毎朝 or a recurring regional observance supply the repetition; one accidental action alone is not a habit.