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The Ultimate GRE Word List & Dictionary

References

Barron
Barron's test preparation materials are renowned and worth investing in. Their word list is probably the most extensive single original list, and is updated regularly: every year there is a new edition, just as there are changes in trends with the GRE test itself every year. The one used as a source for GREdic is at least 5 years old, so you should get the latest edition to keep up with the evolution of the GRE test. (Yes, the GRE test does change over time!)
Princeton Review
"Cracking the GRE" by Princeton Review is probably the reference of choice if you're in for a speedy preparation. Their wordlist is not as extensive as Barron's, but they keep a Hit Parade of must-know words, updated in each new edition. This is probably your best shot at getting some results with a minimal preparation effort. Again, my copy was the 2001 edition, so you will want to get the latest edition to prepare yourself best for the test that you will be facing.
Taisha
As far as I can tell, this is a word list of Chinese origin. It is no longer available at the web site where I found it, but probably traces back to taisha.org
Nandigam
Another resource no longer available online. I found it on a web page at uhaweb.hartford.edu. It was probably compiled by somebody named Nandigam.
Smirnov
This too is a list no longer available online. Apparently, it was compiled by a guy named Oleg Smirnov and was once available at his page at uoregon.edu. I should point out that this list and Nandigam's are nearly identical, one was probably made by amending the other (or they both used a common source).
Webster
If you don't have it, get it! Webster's is a reference nobody can do without (and I don't mean just for GRE prepping). There are many editions to choose from, ranging from pocket to encyclopaedic. Personally, I think a middle one and the biggest one are a nice pair to have. But the unabridged CD-ROM version is also something to consider.
ETS: Practicing to Take the GRE General Test
This is one of the most popular preparation texts. No wonder - ETS is the institution that stands behind the GRE test, and this book is the only test prep guide that contains questions and topics from actual tests administered worldwide. It contains verbal and quantitative questions from seven actual GRE General Tests and sample analytical writing topics from the complete pool of topics for the analytical writing measure. It includes information about the structure of the test, answering procedures, explanations of correct answers for verbal and quantitative questions, sample writing responses with scores, scoring information, a math review, and test-taking strategies.
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