Purity

Purity has various meanings.

Something may exhibit purity if it does not contain foreign material or pollutants; otherwise the object or thing may exhibit impurity.
The purity of a precious metal is the extent to which it is pure metal, not alloy; see assay and carat (purity).
In various religions, certain items are said to lack "purity" or be unclean; see unclean animals and taboo food and drink.
Purity is the codename for the Black Oil virus in The X-files.
A "purity test" is a type of informal questionnaire, which often exhibits off-color humor.
Purity Supermarkets, a brand formerly used for Woolworths Supermarkets in Tasmania.
Purity Distilling Company, the company responsible for the Boston molasses disaster.
A song by the band Slipknot on their first self-titled album