Meaning of admixture

(noun) the state of impairing the quality or reducing the value of something

an additional ingredient that is added by mixing with the base; "the growing medium should be equal parts of sand and loam with an admixture of peat moss and cow manure"; "a large intermixture of sand"

the act of mixing together; "paste made by a mix of flour and water"; "the mixing of sound channels in the recording studio"