adj. im·pur·er, im·pur·est
1. Not pure or clean; contaminated.
2. Not purified by religious rite; unclean.
3. Immoral or sinful: impure thoughts.
4. Mixed with another, usually inferior substance; adulterated.
5. Being a composite of more than one color or mixed with black or white.
6. Deriving from more than one source, style, or convention; eclectic: an impure art form.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.