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

Other days

bubble bath

Bubble Bath Day
ride the wind

Ride The Wind Day
ruby

Ruby Day
nae nae

Nae Nae Day
kiss a ginger

Kiss A Ginger Day
slime

Slime Day
lisp

Lisp Day
aloxolt

Aloxolt Day
first love

First Love Day
lash

Lash Day