(astronomy) A nebula composed of ionized gases which produce visible light (as distinct from a reflection nebula, which reflects the light produced by neighboring stars).

A market-based approach to controlling pollution by providing incentives for reducing the emissions of pollutants.

plural of emission nebula

plural of emission nebula

plural of field emission

The permit to emit carbon dioxide and other greenhouse gases during a specified period.

plural of emission allowance

(physics) A nuclear reaction in which one or more neutrons are emitted. / A form of radioactive decay, where a nucleus with a severe excess of neutrons, emits a neutron.

superlative form of low-emission: most low-emission

Producing fewer pollutants to be emitted into the atmosphere.