An essential amino acid, C6H13NO2, obtained by the hydrolysis of protein by pancreatic enzymes during digestion and necessary for optimal growth in children and for the maintenance of nitrogen balance in adults.
[French : leuc-, leuc- + -ine, -ine.]
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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.