Impure (adjective)

1. Not pure; mixed with other substances.
2. Not morally or spiritually pure; corrupt or tainted.
3. Containing or consisting of impurities.

Origin:

From the latin in- (not) + purus (pure).

Examples:

1. The impure gold was not suitable for making jewelry.
2. The impure water was not safe to drink.
3. The impure air was harmful to breathe.
4. His impure thoughts led to his downfall.
5. The impure motives behind the action were exposed.