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nu·cle·ic acid (n-klēĭk, -klā-, ny-)
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n.
Any of a class of large molecules that are polymers of nucleotides and are found in all living organisms and viruses. The principal nucleic acids, DNA and RNA, are the carriers of hereditary information and control the synthesis of proteins.
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:

    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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