Lewis & Short

1. passĕrīnus, a, um, adj. [1. passer], of or fit for a sparrow: prandium, Pomp. ap. Non. 112, 7 (Com. Rel. p. 213 Rib.).

2. Passĕrīnus, i, m., the name of a very fleet horse, Mart. 7, 7, 10; 12, 36, 12.
In the orthogr PASSARINVS, the name of a circus-horse, Inscr. Grut. 341.