patois

Estimated CEFR level: C2 — Proficiency

Estimated from word frequency; not an official CEFR classification.

Definition

noun a characteristic language of a particular group (as among thieves)
noun a regional dialect of a language (especially French); usually considered substandard

Borrowed from French patois (“regional dialect or language”), c. 1635.

"Mo pas connais," she laughed, dropping into patois. — Shapes that Haunt the Dusk, Unknown
There were many voices, clatter of dishes, chatter of patois. — The Landloper: The Romance of a Man on Foot, Holman Day
In a liquid Spanish-English patois they bade the whites welcome. — Tom Swift and His Giant Telescope, Victor Appleton

slang, cant, jargon, lingo, argot, vernacular

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