Sun ‧ day /ˈsʌndi, -deɪ/ BrE AmE noun [uncountable and countable]
[ Language: Old English ; Origin: sunnandæg ]
1 . ( written abbreviation Sun. ) the day between Saturday and Monday
on Sunday
We’re going to a match on Sunday.
What are you doing Sunday? American English
Sunday morning/afternoon etc
Sunday nights are usually pretty quiet.
last Sunday
It was our wedding anniversary last Sunday.
this Sunday
There’s another antiques market this Sunday.
next Sunday (=Sunday of next week)
We’ll announce the winners next Sunday.
a Sunday (=one of the Sundays in the year)
Finding a dentist on a Sunday can be very difficult.
2 . your Sunday best your best clothes, worn only for special occasions or for church
3 . Sunday driver an insulting expression meaning someone who annoys other people by driving too slowly
⇨ never in a month of Sundays at ↑ month (6)