vocative case
Definition - The case of direct address. You use it when you speak directly to another person or invoke them directly by name.

Example -
I don't give a damn, Scarlet.
(In the above Scarlet is a vocative that shows who is being spoken to.)

Etymology -
The word derives from the Latin vocativus casus, the case of calling (from Latin vocare, to call).
Note: The Latin phrase was coined as a translation of the Greek kletike ptosis, the case of calling (from kletos, called).

Oxford English Dictionary -
The term's first citation is from circa 1440:
"The fyfte is the vocatyf case."
(Gesta Rom. xci. 418 (Add. MS.))

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