(Greek: deep, depth)
2. An instrument for recording contours of deep oceans and seas.
2. A reference to the vertical distribution of organisms in sea.
2. The data derived from such measurement; especially, as compiled in a topographic map.
3. The process of measuring the depths of sea or oceans.
4. The science of measuring ocean depths in order to determine the sea floor topography.
2. A reference to creatures living in the bathyal region of an ocean.
3. Found in the depths of the sea.
The bathypelagic zone receives no sunlight and water pressure is considerable. The abundance and diversity of marine life decreases with depth through this and the lower zones.
2. Thriving in the deep sea to in the depths of the ocean.
The system uses photodiodes to convert the optical signals into electrical signals which are sampled, integrated, and coupled to output terminals for transmission to a surface host vehicle.
Here is more information about bathyphotometry.
2. Plankton that live at a depth below the mesoplankton zone.
3. The plankton in the greater depths of the oceans or seas; especially, of the abyssal zones.
2. A navigable, submersible vessel for exploring the depths of the ocean, having a separate, overhead chamber filled with gasoline for buoyancy and iron or steel weights for ballast.
3. A free-diving vessel used to explore the ocean at great depths.
The original bathyscaphe, constructed in 1948, was made of a cylindrical metal float and a suspended steel ball that could hold two people.
Design improvements allowed the second bathyscaphe in 1960 to descend to a record 10,912 meters (35,791 feet) in the Marianas Trench in the western Pacific Ocean, almost to the deepest level ever sounded on earth.4. A "diving apparatus for reaching great depths", 1947, name coined by its inventor, Swiss "scientific extremist" Professor Auguste Piccard, from Greek bathys, "deep" + skaphe, "boat".