List of Words for Letter ‘O’
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observe To
use one or more of the senses to identify or learn about an object or event.
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occluded front A weather front that occurs when cool air catches up with a warm front and then moves underneath the warm front, creating a wedge of warm air between two masses of cool air.
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opaque Matter
that does not allow light to pass through it.
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organ A
group of two or more types of tissue that work together to carry out one specific function.
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organ system A
group of organs working together.
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organic compound The chemical building blocks of all known living things. All organic compounds contain carbon.
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organism The
diffusion of water through a cell membrane.
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osmosis The diffusion of water through
a cell membrane.
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ozone layer A
layer of ozone gas in Earth’s atmosphere that screens out much of the Sun’s ultraviolet rays.