Statistical glossaries

When you don't know a statistical term, most often you really need to learn more than just that one term. Wikipedia can help, as can textbooks. And Google, as always, can guide you to lots of resources. 

But sometimes all you need is a quick definition. If so, here are some useful statistical glossaries:

	The Data Analysis Brief Book   By R.K.Bock and W.Krischer. The authors work at CERN (high energy physics) so it a very different orientation than the others.
	Hyperstat glossary   Extensive, with a behavioral sciences emphasis.
	StatSoft Glossary   Unlike the other glossaries, many entries here are accompanied by diagrams (some animated).  This glossary has a fairly mathematical orientation.
	Prophet Glossary   Truly a glossary, with short definitions (unlike some of the other resources, which are really encyclopedias). Less comprehensive than the others, but a good place to quickly find a definition.
	MathWorld   MathWorld, created by Eric Weisstein, is an extensive online encylopedia of mathematical information hosted by Wolfram research (makers of Mathematica). It is not (yet) particularly strong in probability and statistics, but you may find what you are looking for. This is a mathematical site, so come here looking for formulae and proofs, not biological insights.
	Ultimate statistics glossary.  Concise definitions, without explanations.