Language or dialect

The term dialect (from Latin , , from the Ancient Greek word , diálektos, "discourse", from , diá, "through" and , légō, "I speak") is used in two distinct ways to refer to two different types of linguistic phenomena:

For example, most of the various regional Romance languages of Italy, often colloquially referred to as Italian "dialects," are, in fact, not actually derived from modern standard Italian, but rather evolved from Vulgar Latin separately and individually from one another and independently of standard Italian, long prior to the diffusion of a national standardized language throughout what is now Italy. These various Latin-derived regional languages are therefore, in a linguistic sense, not truly "dialects" or varieties of the standard Italian language, but are instead better defined as their own separate languages. Conversely, with the spread of standard Italian throughout Italy in the 20th century and the increase in dialect levelling, various regional versions or varieties of standard Italian developed, generally as a mix of national standard Italian with a substratum of local regional languages and local accents. These variations on standard Italian, known as regional Italian, would more appropriately be called "dialects" in accordance with the first linguistic definition of "dialect," as they are in fact derived partially or mostly from standard Italian.

A dialect is distinguished by its vocabulary, grammar, and pronunciation (phonology, including prosody). Where a distinction can be made only in terms of pronunciation (including prosody, or just prosody itself), the term accent may be preferred over dialect. Other types of speech varieties include jargons, which are characterized by differences in lexicon (vocabulary); slang; patois; pidgins; and argots.

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