Noah Webster
Impure
IMPU'RE, adjective [Latin impurus; in and purus, pure.]
1. Not pure; foul; feculent; tinctured; mixed or impregnated with extraneous substance; as impure water or air; impure salt or magnesia.
2. Obscene; as impure language or ideas.
3. Unchaste; lewd; unclean; as impure actions.
4. Defiled by sin or guilt; unholy; as persons.
5. Unhallowed; unholy; as things.
6. Unclean; in a legal sense; not purified according to the ceremonial law of Moses.
IMPU'RE, verb transitive To render foul; to defile. [Not used.]