emis·sion 
/iˈmɪʃən/ noun
plural emis·sions /iˈmɪʃən/ noun 1 [noncount] : the act of producing or sending out something (such as energy or gas) from a source
▪ emission of light ▪ trying to reduce the emission of greenhouse gases 2 [count] : something sent out or given off
▪ The new regulations are intended to reduce auto emissions. [=harmful substances released into the air by automobiles]
▪ emission of light ▪ trying to reduce the emission of greenhouse gases
▪ The new regulations are intended to reduce auto emissions. [=harmful substances released into the air by automobiles]
