boa

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Any of various large, nonvenomous, chiefly tropical snakes of the family Boidae, which includes the python, anaconda, boa constrictor, and other snakes that coil around and suffocate their prey.
2. n. A long fluffy scarf made of soft material, such as fur or feathers.

Century Dictionary and Cyclopedia

1. n. [capitalized] In herpetology, a genus of very large non-venomous serpents, of the family Boidæ, notable for their power of constriction. It was formerly nearly coextensive with the modern family, and included all the boas, anacondas, etc., but is now restricted to certain South American species congeneric with Boa constrictor. The genus includes some of the largest known serpents (sometimes more than 20 feet long), capable of enveloping and crushing mammals as large as a deer.
2. n. In ordinary language, some large serpent, as a boa-constrictor, anaconda, or python; any member of the family Boidæ or Pythonidæ.
3. n. A long and slender cylindrical wrap of fur, worn by women round the neck.

Wiktionary

1. n. Any of a group of large American snakes, of the genus Boa, including the boa constrictor, the emperor boa of Mexico, and the chevalier boa of Peru.
2. n. A type of scarf typically made from feathers.

GNU Webster's 1913

1. n. A genus of large American serpents, including the boa constrictor, the emperor boa of Mexico (Boa imperator), and the chevalier boa of Peru (Boa eques).
2. n. A long, round fur tippet; -- so called from its resemblance in shape to the boa constrictor.

WordNet 3.0

1. n. a long thin fluffy scarf of feathers or fur
2. n. any of several chiefly tropical constrictors with vestigial hind limbs