Lewis & Short

ărĭĕtīnus, a, um, adj. [aries].

  1. I. Of or from a ram, ram’s-: ungula, Plin. 29, 4, 27, § 88: pulmo, id. 30, 8, 22, § 72: cornua, Pall. 4, 10, 28.
  2. II. Similar to a ram’s head: cicer, Col. 2, 10, 20; Plin. 18, 12, 32, § 124; Petr. 35.
  3. III. Arietinum oraculum, an ambiguous oracle (the figure taken from the divergent horns of a ram), Gell. 3, 3, 8 (cf. Serv. ad Verg. A. 4, 196).