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

Other days

donate your hair

Donate Your Hair Day
artists

Artists Day
latina equal pay

Latina Equal Pay Day
get funky

Get Funky Day
polyamory

Polyamory Day
lisp

Lisp Day
gum

Gum Day
first love

First Love Day
bow tie

Bow Tie Day
ormille

Ormille Day