anniversary - birthday
An anniversary is a date when you remember something special that happened on that date in an earlier year.
It's our wedding anniversary today.
They celebrated the 400th anniversary of Shakespeare's birth.
Don't refer to the anniversary of the date when you were born as your ‘anniversary’. You call it your birthday.
On my twelfth birthday I received a letter from my father.
It was 10 December, my daughter's birthday.