Eleventy-one was a word that first appeared in J.R.R. Tolkien's The Fellowship of the Ring. In the book it is hobbit slang for the number one-hundred and eleven. Tolkien uses the word several times in the text of the book. First, on page 44 of a dog-eared old paperback version no longer possessing a cover (or last twenty pages either). The discussion is about the birthday of a significant character, Bilbo Bagins.
Bilbo was going to be eleventy-one, 111, a rather curious number, and a respectable age for a hobbit, (the old Took, himself, had only reached 130); and Frodo was going to the thirty-three, an important number: the date of his 'coming of age'.
Tolkien's biography reveals him to have been a philologist, a person who studies languages. He made up several languages for the characters in his novels. Even so, he never played fast and loose with English. Though his writing style was colorful, it was nearly always direct, and (most of all) proper English. However, he also understood that language evolves and that slang and new word forms are an essential part of a living language. He made English the common tongue of the peoples of Middle-Earth. Thus, inventing eleventy-one for his hobbits was a logical thing to do.
The use of this almost childish construction may have had a purpose beyond simple wordplay, of which Tolkien was fond. In fact, it was probably meant to illustrate the innocence of the hobbit characters as they went about their sheltered lives in the Shire, as well as their love for simple things. He makes this clear when he relates Bilbo's birthday speech, of which we shall reproduce a fragment from page 55 of the tattered tome:
...I am immensely fond of you all, and eleventy-one years is too short a time to live among such excellent and admirable hobbits. (Tremendous outburst of approval.) I don't know half of you half as well as I should like; and I like half of you half as well as you deserve. (This was unexpected and difficult. There was some scattered clapping, but most of them were trying to work it out and see if it came to a compliment.)
Though the last bit was in fun, it certainly proved more than the hobbits wanted to immediately consider. Eleventy-one was a simple idea. All these "half"s multiplied together resulted in muddle and confusion.
Lord of the Rings was published in the mid-twentieth century. Even so it is still commonly read today. Bilbo's birthday is a well-known fictional event and the word "eleventy-one" is commonly used to mean "111" by those who are fond of the book.
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