Mrs. Frisby and the Rats of NIMH: Chapters 15–20

by Robert C. O'Brien
Mrs. Frisby and her children, a family of mice, must leave their home in order to escape the farmer's plow. Because her son Timothy is too sick to leave his bed, Mrs. Frisby enlists the help of a group of super-intelligent rats to help move her family to safety.

Here are links to our lists for the novel: Chapters 1–5, Chapters 6–14, Chapters 15–20, Chapter 21–Epilogue
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Full list of words from this list:

words only definitions & notes
  1. futile
    producing no result or effect
    A few of the rats snarled and tried to bite; I did not, and neither did Jenner; it was too obviously futile.
  2. partition
    a vertical structure that divides or separates
    But our end held only rows of cages on shelves, each cage with a tag on it, and each separated from its neighbors by wooden partitions on both sides.
  3. cower
    crouch or curl up
    I cowered to the back of the cage, which was just what he expected me to do; one hand pressed me flat against the wire wall; then his fingers gripped my shoulders.
  4. at large
    having escaped, especially from confinement
    Obviously the red light was some kind of a warning signal, both outside the door and in—“laboratory animal at large.”
  5. mutation
    an organism with characteristics from chromosomal alteration
    We have a real breakthrough, and since it is DNA, we may very well have a true mutation, a brand new species of rat.
  6. incur
    make oneself subject to
    Mainly he had learned that he could, occasionally at least, jump from his cage and wander around without incurring any anger or injury.
  7. inkling
    a slight suggestion or vague understanding
    But as to what all this was for, none of us had any inkling.
  8. astute
    marked by practical hardheaded intelligence
    Jenner was astute at that sort of thing; he could foresee problems.
  9. plaintive
    expressing sorrow
    It was a clear but plaintive call, the voice of a mouse.
  10. consternation
    sudden shock or dismay that causes confusion
    As you can imagine, this caused a certain consternation, coming at the last minute.
  11. silo
    a cylindrical tower used for storing grain
    In the country there were barns and silos stocked with grain and corn, and chicken houses full of eggs.
  12. cursory
    hasty and without attention to detail; not thorough
    Oh, there was a caretaker-gardener who came three times a week, and once in a while he would check the house in a cursory sort of way.
  13. bramble
    any of various rough thorny shrubs or vines
    They went on until they came to a fork in the tunnel. “Right fork leads out to the blackberry bramble,” said Justin. “Left fork leads to the main hall.”
  14. stockpile
    something kept back or saved for future use
    “We’ve been building these stockpiles for a long time,” he said.
  15. ranger
    an official responsible for managing an area of forest
    There aren’t any roads in the forest, but only a few jeep trails used by rangers, and airplanes are not permitted to fly over it.
Created on Tue Jul 16 16:46:42 EDT 2019 (updated Thu Jul 31 15:52:00 EDT 2025)

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