n. pl. et·y·mons or et·y·ma (-mə)
1. An earlier form of a word in the same language or in an ancestor language. For example, Indo-European *duwo and Old English twā are etymons of Modern English two.
2. A word or morpheme from which compounds and derivatives are formed.
3. A foreign word from which a particular loan word is derived. For example, Latin duo, "two," is an etymon of English duodecimal.
[Latin, from Greek etumon, true sense of a word, from neuter of etumos, true.]
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.