- a snake, Constrictor (Boa) constrictor, of tropical America, noted for its large size and its ability to suffocate a prey by coiling around it.
- any large snake of the boa family, as the python or anaconda.
- a very large snake, Constrictor constrictor, of tropical America and the Caribbean, that kills its prey by constriction: family Boidae (boas)
