Bathysphere

Part of speech: noun

Definitions

1. A hollow, sealed steel sphere lowered by cable into the deep ocean so observers can study marine life at great depths
2. An airtight spherical chamber used for deep-sea exploration, with a viewing window and an external cable that raises and lowers it
3. A strong, round underwater observation chamber designed to withstand immense pressure while people inside watch the depths of the sea

Etymology: The name of the deep-sea diving vessel was not always a common noun. Its famous 1930s namesake, the Bathysphere, was a steel ball lowered on a cable off Bermuda by William Beebe and Otis Barton, and the device's name became a general term for any craft of its kind. The word was built from "bathy-", from Greek "bathys" meaning "deep," and "-sphere," from "sphaira," a ball, so the literal sense is roughly "deep ball." The device itself predates the name. Versions of the sphere were used in the 1890s, but the word bathysphere was coined decades later, after the 1930s dives had made the machine famous. Readers who associate the term with a generic category are thus following the path of a brand-like name that outlived its single example and became a common noun.

Synonyms: diving bell