adj. pur·er, pur·est
a. Having a homogeneous or uniform composition; not mixed: pure oxygen.
b. Free of dirt, pollutants, infectious agents, or other unwanted elements: pure water.
c. Containing nothing inappropriate or extraneous: a pure style of piano playing.
2. Complete; utter: pure folly.
a. Having no moral failing or guilt: "I felt pure and sweet as a new baby" (Sylvia Plath).
b. Chaste; virgin.
4. Of unmixed blood or ancestry.
5. Genetics Produced by self-fertilization or continual inbreeding; homozygous: a pure line.
6. Music Free from discordant qualities: pure tones.
7. Linguistics Articulated with a single unchanging speech sound; monophthongal: a pure vowel.
8. Theoretical; not applied: pure science.
9. Philosophy Free of empirical elements: pure reason.
[Middle English pur, from Old French, from Latin pūrus; see peuə- in the Appendix of Indo-European roots.]
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.