Lewis & Short

Indĭcus, a, um, adj. [India], of India, Indian: elephanti, Ter. Eun. 3, 1, 23: pecudes, Mart. 5, 37, 5: cornu, i. e. ivory, id. 1, 73, 4: aqua, Ov. P. 1, 5, 80: margarita, Petr. 55.
Subst.: Indĭcum, i, n., indigo, a blue pigment for dyeing and painting, Plin. 33, 13, 67, § 163; 35, 6, 26, § 40.