A person who is not a believer in Islam.
[French, from Italian dialectal (Venetian) giaur (with gi- representing palatalized g- in Ottoman Turkish gâvur), from Ottoman Turkish gâvur, alteration of earlier gebr, from Persian gabr, infidel, Zoroastrian, from Arabic kāfir, infidel, from kafr, village, from Aramaic kaprā; see kpr2 in Semitic roots.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 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.