Definition - The dialect of a region's common people; as opposed to the dialect of the upper classes.

1. According to the OED, "French scholars distinguish dialects as the particular forms presented by a language in different regions, so long as there does not exist a common written language. When a common language has become established as the medium of general literature, the dialects lose their literary standing and become patois."

Dr Suess in Jamaican Patois

Etymology -
The word means "rough speech" in French, and it perhaps derives from the Old French patoier, treat roughly.

Oxford English Dictionary -
Its first citation in this sense is from 1643:
"The Jargon and Patois of several Provinces."
(Sir T. Browne Relig. Med. ii. §8)

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