Lewis Short
sĭmĭlĭtas (noun F) : similis a rare form for similitudo
* Likeness, resemblance, similarity: morum, Caecil. ap. Non. 177, 2 (Com. Rel. v. 216 Rib.).—Plur.: naturae rerum similitates,Vitr. 2, 9 med.
Charlton T. Lewis, Charles Short, A Latin Dictionary