Cerberus
Pronunciation : Cer"be*rus
Part of Speech : n.
Etymology : [L. Cerberus (in sense 1), gr.
Definition : 1. (Class. Myth.)
Defn: A monster, in the shape, of a three-headed dog, guarding the entrance into the infernal regions, Hence: Any vigilant custodian or guardian, esp. if surly.
2. (Zo?l.)
Defn: A genus of East Indian serpents, allied to the pythons; the bokadam.
Source : Webster's Unabridged Dictionary, 1913