big day
noun /ˌbɪɡ ˈdeɪ/
/ˌbɪɡ ˈdeɪ/
[usually singular] (informal)- a very important day, especially for a particular person or group
- Saturday promises to be a big day for Irish sport.
- The children enjoyed themselves preparing for their big day.
- a person's wedding day
- Her family travelled to Australia for the big day.