# What does coinfinite mean?

I'm reading up on maximal sets and the word "coinfinite" pops up in the first sentence. I tried searching on Wolfram Mathworld as well as Google, but nothing concrete has come up. What does it mean and in what context can it be used?

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Limited amount of money? ... Less frivolously, I think the suggestion of Gerald Edgar sounds very plausible – Yemon Choi Sep 14 '10 at 21:07
Coinfinito would mean completely broke. – Will Jagy Sep 14 '10 at 22:36

## 2 Answers

Perhaps it means the complement is infinite. Certainly "cofinite" and "cocountable" are used this way.

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Yes, this is the standard usage. – Andrés Caicedo Sep 14 '10 at 21:08
Thank you, make sense :) – mahmoudimus Sep 14 '10 at 21:12
Comathematician is a machine for turning cotheorems into fee. – Victor Protsak Sep 14 '10 at 21:25
On the other hand, 'cofinite volume' usually refers to a quotient space having finite volume. – Colin Reid Sep 14 '10 at 22:13

See Wikipedia article "Cofiniteness".

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That article has no mention of "coinfinite" however. – Gerald Edgar Sep 15 '10 at 2:15
@Gerald Edgar: That's right, sorry, I seem to have misread the original question. – MikeC Sep 15 '10 at 5:01