Difficult GRE Words - Group 6

[Esc] (1)
a. impossible or difficult to perceive by the mind or senses

[Esc] (2)
a. penetrating, clear, and sharp, as in operation or expression

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a. impossible to remove, erase, or wash away; permanent

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a. cut in the edge into points or inequalities, like teeth; having an uneven, irregular border

[Esc] (5)
a. unfriendly; hostile; harmful; detrimental

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a. stopping and starting at intervals; alternately containing and empty of water

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a. relating to essential nature of a thing; inherent; built-in

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v. make invalid; nullify

[Esc] (9)
v. give vigor to; give life and energy to; strengthen; animate

[Esc] (10)
n. prayer for help; calling upon as reference or support