The act of debasing or the state of being debased; a lowering or degradation, especially in character or quality.
The lowering of the value of a currency by reducing the amount of valuable metal in the coins.
Moral or spiritual corruption; impurity, degradation, defilement.
Physical contamination, now especially the contamination of the environment by harmful substances, or by disruptive levels of noise, light etc.
Something that pollutes; a pollutant.