contamination
n. C / Un. the process of making something dirty, dangerous, or impure by adding something else to it. It often refers to water, food, or the environment being ruined by chemicals or bacteria.
n. the presence of an unwanted constituent, harmful substance, or impurity in a material, physical body, or natural environment. In linguistics, it refers to the process by which one word or form is influenced by another related form, leading to a change in its structure.
The city warned residents about the contamination of the local river.
Strict laboratory protocols are necessary to prevent the contamination of blood samples with outside bacteria.
Environmental scientists are currently assessing the long-term effects of soil contamination caused by the industrial runoff from the abandoned factory site.
From Latin contāminātiōnem.
Uncountable when referring to the general state of being impure; countable when referring to specific instances or types of pollutants.