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Webster 1913 Edition
Cerberus
Cer′be-rus
,Noun.
[L. Cerberus (in sense 1), gr. [GREEK].]
1.
(Class. Myth.)
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.
(Zool.)
A genus of East Indian serpents, allied to the pythons; the bokadam.