Unbirthday

An unbirthday (originally written un-birthday) is an event that is typically celebrated on any or all of the 364 (365 on leap years) days in which it is not the person's birthday. It is a neologism coined by Lewis Carroll in his Through the Looking-Glass, giving rise to "The Unbirthday Song" in the 1951 Disney animated feature film Alice in Wonderland.

One's unbirthday should not be confused with one's half-birthday, which only occurs once a year.

In Through the Looking-Glass, Humpty Dumpty is wearing a cravat (which Alice at first mistakes for a belt) which he says was given to him as an "un-birthday present" by the White King and Queen. He then has Alice calculate the number of unbirthdays in a year.

In the film Alice in Wonderland, Alice stumbles upon the Mad Hatter, the March Hare and the Dormouse having an unbirthday party and singing "The Unbirthday Song" (music and lyrics by Mack David, Al Hoffman and Jerry Livingston). Alice at first doesn't realize what an unbirthday is; when the Mad Hatter explains it to her, she realizes it is her unbirthday as well, and receives an unbirthday cake from the Mad Hatter. The scene from the film combines the idea of an unbirthday introduced in Through the Looking-Glass with the "Mad Tea Party" described in Alice's Adventures in Wonderland.

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