one of two forms that coelenterates take: is the free-swimming sexual stage in the life cycle of a coelenterate and has a gelatinous umbrella-shaped body and tentacles
(Greek mythology) a woman transformed into a Gorgon by Athena; she was slain by Perseus
any of various small animals or insects that are pests; e.g. cockroaches or rats; "cereals must be protected from mice and other vermin"; "he examined the child's head for vermin"; "boys in the village have probably been shooting vermin"