tr.v. in·fixed, in·fix·ing, in·fix·es
1. To fix in the mind; instill.
2. Linguistics To insert (a morphological element) into the body of a word.
An inflectional or derivational element appearing in the body of a word. For example, in Tagalog, the active verb sulat, "write," can be converted to a passive, "written," by inserting the infix -in-, yielding sinulat.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 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.