This is the 11672nd most frequent German word.
sunday
The German word for "Sunday" is "Sonntag," meaning the first day of the week, traditionally a day of rest and worship.
Here, 'Sonntag' is used as a noun indicating the specific day of the week when the activity occurs.
Am Sonntag gehe ich oft spazieren.
On Sunday, I often go for a walk.
In this example, 'Sonntags' is used in its adverbial form to refer to recurring activity that happens on Sundays in general.
Sonntags sind die Geschäfte oft geschlossen.
On Sundays, shops are often closed.
The word 'Sonntags' is included in a genitive phrase showing possession or inclusion.