sol·e·cism (sŏlĭ-sĭz′əm, sōlĭ-)
1. A nonstandard usage or grammatical construction.
2. A violation of etiquette.
3. An impropriety, mistake, or incongruity.
[Latin soloecismus, from Greek soloikismos, from soloikizein, to speak incorrectly, from soloikos, speaking incorrectly, after Soloi (Soli), an Athenian colony in Cilicia where a dialect regarded as substandard was spoken.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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.