Ambit
Noun.
1. Circuit, compass.
2. The bounds or limits of a place or district.
3. A sphere of action, expression, or influence: scope.
[Origin: Middle English, from Latin ambitus, from ambire.]
(1597)
“And you do not?” Andso said, straightening. The captain was edging into blasphemy, and that, at least, was in the priest’s ambit. “Do you doubt the Bishopry, Captain?” – The God Engines, John Scalzi.
If I may ask a question out of pure curiosity, have the words quoted from books come about because you first encountered them in the pages of these books?
No, it wouldn’t be a case where I was unacquainted with a word, that doesn’t happen often! :D However, certain words do strike me when reading, as interesting, not often used, or I want to learn more about their origin, or what particular context may be in play with a word.
I have a nook tablet, and it has a nifty app which keeps all your look-ups, and the book you were reading at the time.