1. The act, process, or result of classifying.
2. A category or class.
3. Biology The systematic grouping of organisms into categories on the basis of evolutionary or structural relationships between them; taxonomy.
clas′si·fi·ca·tori·ly (klăs′ə-fĭ-kə-tôrə-lē, klə-sĭf′ĭ-) adv.
classi·fi·ca·to′ry (klăsə-fĭ-kə-tôr′ē, klə-sĭfĭ-, klăs′ə-fĭ-kātə-rē) adj.
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.