a. A regional or social variety of a language distinguished by pronunciation, grammar, or vocabulary, especially a variety of speech differing from the standard literary language or speech pattern of the culture in which it exists: Cockney is a dialect of English.
b. A variety of language that with other varieties constitutes a single language of which no single variety is standard: the dialects of Ancient Greek.
2. The language peculiar to the members of a group, especially in an occupation; jargon: the dialect of science.
3. The manner or style of expressing oneself in language or the arts.
4. A language considered as part of a larger family of languages or a linguistic branch. Not in scientific use: Spanish and French are Romance dialects.
[French dialecte, from Old French, from Latin dialectus, form of speech, from Greek dialektos, speech, from dialegesthai, to discourse, use a dialect : dia-, between, over; see DIA- + legesthai, middle voice of legein, to speak; see leg- in the Appendix of Indo-European roots.]
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.