1. cerberus - Noun
2. Cerberus - Proper noun
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.
A genus of East Indian serpents, allied to the pythons; the bokadam.
Source: Webster's dictionaryHence, loathèd Melancholy, Of Cerberus and blackest Midnight born, In Stygian cave forlorn, 'Mongst horrid shapes, and shrieks, and sights unholy. John Milton
590–570 BC) LIMC Herakles 2621 (Smallwood, p. 92), seems to show a single lion-headed Cerberus, with snake (open-mouthed) over his back. Source: Internet
According to Smallwood, the identification as Heracles and Cerberus is "suggested by Dunbabin, taken as certain by Schäfer" (p. 92), and "too little of the fragment is preserved for a secure identification". Source: Internet
A mid sixth century BC Laconian cup, by the Hunt Painter, adds several new features to the scene which also become common in later works: three heads, a snake tail, Cerberus' chain and Heracles' club. Source: Internet
After having stolen Helen, to be Theseus' wife, Theseus and Perithous, attempt to abduct Kore, for Perithous, but Aidoneus catches the two heroes, imprisons Theseus, and feeds Perithous to Cerberus. Source: Internet
After searching the entire Peloponnesus, Heracles found where it was said Cerberus was being held, went down into the cave, and brought up Cerberus, after which it was said: "Heracles descended through the cave into Hades and brought up Cerberus." Source: Internet