1. Vocabulary from FREAK THE MIGHTY
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2. Has not been conquered or overcome
unvanquished
Book:
"I never had a brain until Freak came along … and that's the truth … . The unvanquished truth, is how Freak would say it, … ."
Part of Speech:
Adjective
Definition:
Has not been conquered or overcome
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3. prehistoric
Book: "You can see … Grim with no front teeth, grinning at the camera and yanking back on his prehistoric slingshot." Part of Speech: Adjective Definition: Very old or out of date

4. Ol' Blue Eyes (Frank Sinatra)
sobriquet
Ol' Blue Eyes (Frank Sinatra)
Book: "Grim would be, I suppose, a sobriquet for your grandfather, …" Part of Speech: Noun Definition: A person's nickname
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5. demeanor
Book: "Grim would be, I suppose, a sobriquet for your grandfather, based on his demeanor." Part of Speech: Noun Definition: Outward behaviour

6. postulate
Book: "I merely postulated that you call your grandfather 'Grim' because he's grim." Part of Speech: Verb Definition: A thing suggested or assumed as true as the basis for reasoning