D defs.my
Entry 2 senses Webster, 1913

Cerberus

· Cer·be·rus · IPA /ˈsɝbəɹəs/
01 n. A monster, in the shape of a three-headed dog, guarding the entrance into the infernal regions, Hence: Any vigilant custodian or guardian, …
  1. 1.
    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.(Class. Myth.)
  2. 2.
    A genus of East Indian serpents, allied to the pythons; the bokadam.(Zool.)