National Holiday
Festival Day
noun, の adjective
The day you have a festival is a national holiday. That way everyone can come to celebrate without worrying about going to school or work. This is also known as a festival day (pretty obvious, right?).
さいじつ
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
その祭日の予定はまだありません。
I don't have any plans for that festival day.
祭日なのに、仕事なの？
Do you have to work even though it's a national holiday?
祭日だってことを忘れていて、会社に来てしまった。
I forgot it was a holiday and I came to the office.