tau·rine 2 (tôrēn′)
An amino acid, C2H7NO3S, not found in proteins, that is synthesized in the liver from cysteine, is found in bile and other body fluids and tissues, and has a variety of physiological functions.
[Greek tauros, bull (from its having been obtained first from ox bile); see tauro- in the Appendix of Indo-European roots + -INE2.]
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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.