Lewis & Short

Brachmānae, ārum; -māni, ōrum, and -mānes, ium, m., = Βραχμᾶνες [Engl. Brahmins], the priests and learned caste of the Hindoos, the present Brahmins; form Brachmanae, Tert. Apol. 42.
Form Brachmani, Amm. 23, 6, 33; 28, 1, 13.
Gen. Brachmanūm, App. Flor. 2, n. 15 (in Plin. 6, 17, 21, § 64, mentioned as separate tribes or nations: multarum gentium cognomen Brachmanae).