In several lands, this is "a day set aside for public celebration of an anniversary connected with the beginnings of national independence."  - Merriam-Webster's Unabridged Dictionary.
Emazweni amanengi "umkhosi lo ngowokuthakazelela usuku lapho ilizwe elaqalisa khona ukuzibusa."  - Merriam-Webster's Unabridged Dictionary.