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

Other days

bounce

Bounce Day
kiss a ginger

Kiss A Ginger Day
martini

Martini Day
first love

First Love Day
kale

Kale Day
bow tie

Bow Tie Day
buddy

Buddy Day
artists

Artists Day
frozen yogurt

Frozen Yogurt Day
tulip

Tulip Day