emission · noun C or U /iːˈmɪʃ.ən/Full view
C1 when gas, heat, light, etc. is sent out into the air, or an amount of gas, heat, light, etc. that is sent out
Dictionary example:

Carbon dioxide emissions will be reduced by 20%.

Learner example:

One may argue from the point of linking CO2 emissions to other known pollutants, like industry, but recent studies have shown traffic to be [one of] the most important causes of air pollution. (International English Language Testing System; C1; Malayalam)

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