1. Apocryphal-of doubtful authenticity
ə/päkrəfəl/
adjective
These guys are made up characters. They are not real.
 apoc·ry·phal·ness noun
Someone made up an apocryphal story about the president’s childhood.

2. Temerity (NOUN)-boldness
She had the temerity to ask my boyfriend if she could go out with him should he and I ever break up.
Good way to remember: Temerity sounds like timid but it’s actually the opposite—boldness and brave.

3. Imminent (ADJ)-threatening to occur
We are in imminent danger of the thunderstorm coming this afternoon.
Good way to remember- Imminent sounds like immediately which means it’s going to happen.
These patients are facing imminent death.

4. Mordant(ADJ)-bitterly sarcastic
A mordant review of the movie that compared it to having one's teeth pulled for two hours.

5. Elocution (NOUN)-the art of public speaking
the oft-told story that he practiced elocution by learning to speak with a mouth full of pebbles.
Good way to remember-Elocution sounds like eloquent which has a similar meaning.

6. Exorbitant-excessive
<the cost of our stay was so exorbitant you would have thought that we had bought the hotel and not just spent a few nights there>
Good way to remember-excessive and exorbitant sound similar.

7. Arcane (ADJ)-understood only by a few
grammatical rules that seem arcane to generations of students who were never taught grammar in the first place.

8. Apropos (Adverb)-relevant
I went up to New York last weekend; apropos, have you seen your New York cousins lately?
Good way to remember- French à propos, literally, to the purpose

9. Incisive (Adj)-intellectually keen
She's known for her incisive mind and quick wit.

10. Diatribe (Noun)-bitter speech
a bitter diatribe about how unfair the tax system is