sillybus, i, m., = σίλλυβον,
a kind of thistle , Plin. 22, 22, 42, § 85; 26, 7, 25, § 40 (but the true reading, Cic. Att. 4, 5, 3; 4, 8, a, 2, is sittybus, q. v.).
sillybus ī, m , see sittybos. ...
An Elementary Latin Dictionary