mo·res (môrāz′, -ēz)
1. The accepted traditional customs and usages of a particular social group.
2. Moral attitudes.
3. Manners; ways.
[Latin mōrēs, pl. of mōs, custom; see mē-1 in the Appendix of Indo-European roots.]
Usage Note: Although educated 19th-century speakers of English would pronounce mores as (môrēz) according to the customary pronunciation of Latin in English-speaking countries at that time, 75 percent of the Usage Panel in 2005 found this same pronunciation unacceptable (although 5 percent actually preferred it). Nowadays, the accepted pronunciation is (môrāz), with a long a as in days and a (z) sound at the end. It is incorrect to pronounce it as a single syllable (môrz), and the pronunciation ending with an (s) sound, which more closely resembles the way the Latin word was actually pronounced by the Romans, may sound pretentious.
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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.