Oops, it doesn't look like 'corbean day' is a national day..

Other days

gum

Gum Day
coffee

Coffee Day
girl friend

Girl Friend Day
unicorn

Unicorn Day
one

One Day
first love

First Love Day
nae nae

Nae Nae Day
bow tie

Bow Tie Day
boba

Boba Day
azonto is acceptable

Azonto Is Acceptable Day