common GRE confusing words - part 1

nitpicky: FASTIDIOUS /fæsˈtɪd.i.əs/
not serious is FACETIOUS  /fəˈsiː.ʃəs/
FASTIDIOUS /fæsˈtɪd.i.əs/: very attentive to and concerned about accuracy and detail.

He is very fastidious about how a suitcase should be packed.

They were too fastidious to eat in a fast-food restaurant.
facetious /fəˈsiː.ʃəs/ (a): not serious about a serious subject, in an attempt to be amusing or to appear clever:

He's just being facetious

facetious remarks

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revengeful: VINDICTIVE /vɪnˈdɪk.tɪv/
justify, clear doubt is VINDICATE 

revengeful: vindictive 

revenge: (v) to payback
In the film 'Cape Fear', a lawyer's family is threatened by a vindictive former prisoner.
The decision to include Morris in the team was completely vindicated when he scored three goals.

The investigation vindicated her complaint about the newspaper.
They said they welcomed the trial as a chance to vindicate themselves.

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postpone =delay: to DEFER
prevent, discourage: DETER /dɪˈtɜːʳ/

My bank has agreed to defer the repayments on my loan while I'm still a student.

 Can we defer making a decision until next week?

These measures are designed to deter an enemy attack.
High prices are deterring many young people from buying houses.
deterrent /dɪˈter.ənt/ (n):  something which deters people from doing something:
a nuclear deterrent

deterrent /dɪˈter.ənt/ (a)

a deterrent effect

*

still existing is EXTANT
no longer in existence: EXTINCT

.

A limited number of documents from the period are still extant.

There is concern that the giant panda will soon become extinct.
The extinction of the dinosaurs occurred millions of years ago.