1.nounAny of several species of generalist predatory Carnivores in the family Herpestidae; the various species range in size from rats to large cats. The Indian mongoose is noted as a predator of venomous snakes, though other mongoose species have similar habits.
2.nounAny species of Malagasy mongoose; only distantly related to the Herpestidae, these are members of the family Eupleridae; they resemble mongooses in appearance and habits, but have larger ears and ringed tails.