Sunday, the first day of the week, particularly as the Christian Sabbath.
The first day of the week in many religious traditions, and the seventh day of the week in systems using the ISO 8601 standard; the Christian Sabbath; the Lord's Day; it follows Saturday and precedes Monday.
A comic strip published in a Sunday newspaper.
A newspaper published on Sunday.
To spend Sunday (at a certain place, with a certain person or people, etc.).
On Sundays.