Grade 7: "A Sound of Thunder" by Ray Bradbury

In the year 2055, Time Travel, Inc., offers wealthy adventurers the chance to travel back in time to hunt extinct animals. A man named Eckels pays a huge sum to travel back to the Mesozoic era to hunt a Tyrannosaurus Rex, but he is warned of the catastrophic consequences that could result with even the smallest misstep.
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Full list of words from this list:

words only definitions & notes
  1. safari
    a journey to hunt or see animals, especially in Africa
    “Does this safari guarantee I come back alive?”
    “We guarantee nothing,” said the official, “except the dinosaurs.”
  2. annihilate
    do away with completely, without leaving a trace
    “With a stamp of your foot, you annihilate first one, then a dozen, then a thousand, a million, a billion possible mice!”
  3. expendable
    suitable to be used up
    "...And the caveman, please note, is not just any expendable man, no! He is an entire future nation. From his loins would have sprung ten sons. From their loins one hundred sons, and thus onward to a civilization...."
  4. teeming
    abundantly filled with especially living things
    "...Perhaps Rome never rises on its seven hills. Perhaps Europe is forever a dark forest, and only Asia waxes healthy and teeming. Step on a mouse and you crush the Pyramids. Step on a mouse and you leave your print, like a Grand Canyon, across Eternity...."
  5. correlate
    bring into a mutual, complementary, or reciprocal relation
    "...I shoot a paint bomb. It leaves a red patch on his side. We can’t miss it. Then I correlate our arrival in the Past so that we meet the Monster not more than two minutes before he would have died anyway...."
  6. paradox
    a statement that contradicts itself
    "That’d be a paradox," said the latter. "Time doesn’t permit that sort of mess—a man meeting himself."
  7. pterodactyl
    extinct flying reptile
    Sounds like music and sounds like flying tents filled the sky, and those were pterodactyls soaring with cavernous gray wings, gigantic bats of delirium and night fever.
  8. reptilian
    of or relating to cold-blooded vertebrates with scaly skin
    Out of the mist, one hundred yards away, came Tyrannosaurus Rex.
    “It,” whispered Eckels. “It……
    “Sh!”
    It came on great oiled, resilient, striding legs. It towered thirty feet above half of the trees, a great evil god, folding its delicate watchmaker’s claws close to its oily reptilian chest.
  9. warily
    in a manner marked by keen caution and watchful prudence
    It ran with a gliding ballet step, far too poised and balanced for its ten tons. It moved into a sunlit area warily, its beautifully reptilian hands feeling the air.
  10. remit
    send in payment
    “We were fools to come. This is impossible.”
    “Shut up!” hissed Travis.
    “Nightmare.”
    “Turn around,” commanded Travis. “Walk quietly to the Machine. We’ll remit half your fee.”
  11. undulate
    move in a wavy pattern or with a rising and falling motion
    In the slime, tiny insects wriggled, so that the entire body seemed to twitch and undulate, even while the monster itself did not move.
  12. finality
    the quality of being definitely settled
    Another cracking sound. Overhead, a gigantic tree branch broke from its heavy mooring, fell. It crashed upon the dead beast with finality.
  13. primeval
    having existed from the beginning
    The jungle was alive again, full of the old tremorings and bird cries. Eckels turned slowly to regard the primeval garbage dump, that hill of nightmares and terror. After a long time, like a sleepwalker he shuffled out along the Path.
  14. subliminal
    below the threshold of conscious perception
    Eckels stood smelling of the air, and there was a thing to the air, a chemical taint so subtle, so slight, that only a faint cry of his subliminal senses warned him it was there.
  15. exquisite
    delicately beautiful
    It fell to the floor, an exquisite thing, a small thing that could upset balances and knock down a line of small dominoes and then big dominoes and then gigantic dominoes, all down the years across Time. Eckels’ mind whirled. It couldn’t change things. Killing one butterfly couldn’t be that important! Could it?
Created on Mon Apr 06 21:00:41 EDT 2026 (updated Mon Apr 27 17:04:54 EDT 2026)

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