late 14c., "large snake," from Latin boa, type of large serpent mentioned in Pliny's "Natural History;" origin unknown (in Middle English folk etymology associated with Greek bous "ox"). Extension to "snake-like coil of fur worn by ladies" is from 1836. Boa constrictor so called from 1788.
[IBM] Any one of the fat cables that lurk under the floor in a dinosaur pen. Possibly so called because they display a ferocious life of their own when you try to lay them straight and flat after they have been coiled for some time. It is rumored within IBM that channel cables for the 370 are limited to 200 feet because beyond that length the boas get dangerous --- and it is worth noting that one of the major cable makers uses the trademark "Anaconda".
[Jargon File]