A freshwater mussel, usually edible, of the order Unionida in subclass Palaeoheterodonta.
A saltwater mussel, usually edible, of the order Mytilida in subclass Pteriomorphia.
Any of certain other bivalves of somewhat similar appearance, such as the zebra mussel and quagga mussel of the family Dreissenidae in subclass Heterodonta.
A similar part in some invertebrates.
The vulva, or the vulva and the vaginal passage collectively.
A sheathlike structure, such as the leaf of a grass that surrounds a stem.
The passage leading from the opening of the vulva to the cervix of the uterus for copulation and childbirth in female mammals.
A coward; a weakling; a pussy.