List of Words for Letter ‘O’
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orbit The path one object travels around another object.
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organ A group of tissues working together to do a certain job.
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organ system A group of organs that work together to do a certain job.
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organism Any living thing that can carry out its life on its own.
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outer core A liquid layer of iron and nickel below Earth’s mantle. A form of oxygen gas that makes a layer in the atmosphere that screens out much of the Sun’s ultraviolet rays.
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ozone A form of
oxygen gas that makes a
layer in the atmosphere that
screens out much of the Sun’s
ultraviolet rays.