I hate Urban Dictionary.

Here's a definition I wrote which was rejected:

Hilbert space

A complete inner product space. Since every inner product defines a norm, a Hilbert space is necessarily a Banach space.

Up to equivalence of norms, there's only one distinct n-dimensional Hilbert space for each n, namely R^n.

The space of all continuous real-valued functions on the closed interval from 0 to 1, with the inner product given by the integral of pointwise absolute-value products, is an infinite-dimensional Hilbert space.

(I used the circumlocution "the closed interval from 0 to 1" because there's no way to insert a literal opening square bracket in an Urban Dictionary definition.)

By contrast, I got away with this one:

http://www.***************.com/define.php?term=complete

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Many real-world problems are contingency problems, because exact prediction is impossible. For this reason, many people keep their eyes open while driving.

Why.
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x is an irrational number if and only if the set { nx mod 1 | n is a natural number } is dense in [0,1].

I have no idea.

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Many real-world problems are contingency problems, because exact prediction is impossible. For this reason, many people keep their eyes open while driving.

To be precise, the response I got was:

Thanks for your definition of Hilbert space!

Editors reviewed your entry and have decided to not publish it.

To get a better idea of what editors publish and reject, sign up as an Urban Dictionary Editor here: http://editor.***************.com/

I've been an editor, I know the rules, and I followed 'em.

I'm tempted to just resubmit it and see if it gets accepted the second time round.

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Many real-world problems are contingency problems, because exact prediction is impossible. For this reason, many people keep their eyes open while driving.

Regardless of what you wanted to put up, them shutting you down on it is ridiculous. I've seen definitions of words not even slang like "Curtis." One of the definitions was "A douchebag" or something for that one.
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Holy **** we're in the Matrix? - Willis

Urban Dictionary is not meant to be an accurate dictionary, except for slang. Your definition was rejected because it's an actual definition. That's not what they want. Basically you have to be amusing to get into Urban Dictionary, and the definition of Hilbert Space is not amusing... or is it? Is there some higher-maths joke I'm missing?

The Rules say "Any word from your life belongs here, so don't reject an entry just because it's in a real dictionary." The definition I submitted doesn't really contain a joke; the joke is just getting advanced mathematics onto a website that's mostly concerned with describing obscure sex positions.

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Many real-world problems are contingency problems, because exact prediction is impossible. For this reason, many people keep their eyes open while driving.

I resubmitted it and it was accepted.

http://www.***************.com/define.php?term=Hilbert%20space

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Many real-world problems are contingency problems, because exact prediction is impossible. For this reason, many people keep their eyes open while driving.