日曜日

1. Origins, structure, and basic meaning

• Structure: The weekday compound 日曜日 (にちようび) uses 日, 曜, and 日 to name Sunday.
• Basic usage: 日曜日は makes Sunday a contrastive topic, while 日曜日に marks the time of an event.

2. Common pitfalls and similar expressions

• Topic and point in time
  • The weekday name by itself does not necessarily mean that something happens every week.