ENERGY

(adjective) relating to forms of energy that are produced using the sun, wind, etc., or from crops, rather than those using fuels such as oil or coal

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(adjective) not harmful to the environment

(adjective) able or likely to cause harm or death, or unpleasant problems

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(noun) a condition or situation that causes problems, especially one that causes something or someone to be less successful than other things or people

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