What is the meaning of "Dan" in "Lubandan"

Birth means the 13th day of June in the lunar calendar, and it is called Lubandan.

Looking through the dictionary, I can't see that "Dan" means "birthday"

Therefore, "Lu Bandan" may be the mistake of "Lu Bandan's birthday".

If you have to be reasonable, then "Lu Bandan" can only be understood as "Lu Bandan", or a troupe in Shandong, in which the actress is called "Lu Bandan".

On the other hand, if the meaning of "Luban Memorial Day" is abbreviated as "Luban Day" or "Luban Dan", it seems a little ordinary. What is the meaning of "Dan" in "Lubandan"? Birth means the 13th day of June in the lunar calendar, and it is called Lubandan.