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chi·mer·ic (kī-mĕrĭk, -mîr-)
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adj.
1. Relating to or being an organism, part, or molecule that is a chimera: chimeric mice; chimeric proteins.
2. Relating to a monoclonal antibody produced from the cells of a nonhuman organism, usually a mouse, in which a portion of the antibody has been replaced with a human sequence of amino acids. This is done in the laboratory by replacing part of the DNA sequence in the nonhuman cells with a sequence of human DNA.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. 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:

    Indo-European Roots

    Semitic Roots

    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.

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