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ar·gi·nine

(ärjə-nēn′)

An amino acid, C₆H₁₄N₄O₂, obtained from the hydrolysis or digestion of plant and animal protein.

[German Arginin, possibly from Greek arginoeis, bright; see arg- in the Appendix of Indo-European roots.]

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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