If you have tried some of the “vocabulary” questions on the GRE, you will know what I mean when I say many of them are way out there! Some I myself have never encountered before! But, that said, there is an approach that can maximize your score.
Here are some considerations:
Don’t consider it a vocabulary test. A vocabulary test implies you either know or don’t know the meaning of the words. In reality, you will be making educated guesses for many of the questions. I recommend GRE Vocab Capacity, by McElroy and Kotchian, a book of 1300 words commonly seen on previous GRE exams, with mnemonic devices to remember them. The idea is, you don’t try to memorize the words; you just read through the book.
You can count on more than half of the questions to need “unpacking.” The GRE brings contextual clues to a new level. On many questions, you will need to unravel some logic, such as double negatives.
An effective method for filling in the blanks is to cover up the answer choices and think of your own word or phrase to go in the blank(s). I have seen students almost double their correct answers doing this.
Expect to do a fair amount of guessing and using the process of elimination.