Definition - The language used in a particular place.

Example -
Parisian French is the vernacular of Paris.

Etymology -
The word derives from the Latin vernaculus, domestic or native (from verna, home-born slave).

Oxford English Dictionary -
Its first citation is from a1706:
"It is written in the Chaldaeo-Syriac, which was … the vernacular of our Lord."
(Evelyn Hist. Relig. (1850) I. 427)

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