Scientists Say

A weekly word defined, in a sentence and in context. Click here to find the alphabetized list.

  1. Physics

    Scientists Say: Dark Energy

    Dark energy is the unknown force causing the universe to expand faster and faster.

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  2. Life

    Scientists Say: Eukaryote

    Eukaryotes are living things whose cells package their genetic material inside a pouch called a nucleus.

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  3. Earth

    Scientists Say: Pollution

    Pollution is any substance or form of energy released into the environment that is harmful to people or other living creatures.

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  4. Math

    Scientists Say: Geometry

    Geometry is math that allows people to measure, analyze and compare figures in space.

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  5. Chemistry

    Scientists Say: Decay

    This word can refer to rotting flesh or the transformation of radioactive atoms.

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  6. Physics

    Scientists Say: Voltage

    Voltage is a measure of how much electricity is available to power devices.

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  7. Life

    Scientists Say: Bacteria

    Bacteria get a bad rap for making people sick, but only a tiny portion of these single-celled creatures cause disease.

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  8. Chemistry

    Scientists Say: Silicon

    The chemical element silicon is used to make everything from bricks to cookware to electronics.

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  9. Space

    Scientists Say: Solar wind

    This is a powerful gust of charged particles that flows out from the sun through the solar system.

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  10. Animals

    Scientists Say: Adaptation

    This word refers to a feature of a living thing that helps it better survive in its environment — or the process of that feature evolving in a population.

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  11. Earth

    Scientists Say: Savanna

    Savannas exist where there is more rainfall than in a desert, but less than in a forest.

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  12. Chemistry

    Scientists Say: Experiment

    An experiment is a set of procedures to learn about the world — and an important part of the scientific process.

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