n. pl. mod·u·li (-lī′)
1. Abbr. m or M Physics A quantity that expresses the degree to which a substance possesses a property, such as elasticity.
a. The square root of the product of a complex number and its complex conjugate.
b. Abbr. mod A natural number used as a specified divisor in modular arithmetic.
c. The number by which a logarithm in one system must be multiplied to obtain the corresponding logarithm in another system.
[Latin, diminutive of modus, measure; see med- in the Appendix of Indo-European roots.]
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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.