Any of a class of enzymes that catalyze the cleavage of bonds without hydrolysis or oxidation, often resulting in a new double bond or ring structure, or that catalyze the addition of chemical groups to double bonds.
[Greek lūein, to loosen; see leu- in the Appendix of Indo-European roots + -ASE.]
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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.