langue d'oc
Definition - The version of Old French that was used south of the Loire river in France, e.g. in Provence and Languedoc.
Note: The version of Old French that was spoken north of the Loire was called langue d'oïl.

Example -

Etymology -
Langue d'oc was so called because its speakers used the word oc (which derives from the Latin hoc) for yes.
Note: This is in contrast to the speakers of Langue d'oïl who used the word oïl (from the Latin hoc ille) for yes.

Oxford English Dictionary -
The term's first citation is from 1703:
"I more approve of the Etymology of those who observe, that, time out of mind, the French have been distinguish'd into Langue d'Ouy, and Langue d'Oc, that is, into such as say Ouy, and such as say Oc for Yes; the first living on this, and the other on that side the River Loire."
(Acct. Theatre of War in France, being a Geogr. & Hist. Descr. Languedoc 3,)

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