早寝

1. Origins, structure, and basic meaning

• Structure: 早寝 is read as はやね and is a noun formed from 早い and 寝, referring to going to bed early.
• Basic usage: It is used for intentionally retiring early before an early departure or for an established early-bedtime habit.

2. Common pitfalls and similar expressions

• 早寝する
  • Add する in 早寝する to state the action of going to bed early that night.
• Habit as the subject
  • In 早寝が習慣だ, early bedtime itself is the habit, not a single accidental instance of falling asleep quickly.