vŏcātīvus

a, um, adj.

voco

I. of or belonging to calling: casus, the vocative case, in gram., Gell. 14, 5, 1 sq. al.—As subst.: vŏcātīvus, i, m., the vocative case, Charis. p. 11 P.; Prisc. p. 671 ib. al.
Lewis & Short
A Latin Dictionary, 1879
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