batho-, bathy-

In geology, the lateral distribution and character of underwater sedimentary strata: Part of Sally's geology class dealt with the bathymetric biofacies of the ocean.

A topographic map of the surface of the sea floor: The professor showed the students the latest bathymetric chart of the Pacific Ocean.

Relating to measurements of the depths of oceans or lakes: Experts were able to map the ocean bed using bathymetrical technology and were amazed at the underwater terrain.

1. The measurement of the depths of oceans, seas, or other large bodies of water: Since Thomas was interested in oceanography, he learned more about bathymetry and found out that it was the underwater equivalent to "hypsometry" or "topography".
2. The data derived from such measurements: The material obtained from bathymetry, and compiled in a topographic map, provides good information for navigation.
3. The science of measuring ocean depths in order to determine the sea floor topography: Judy decided to study bathymetry, since she was very interested in oceanography and vessels.

A reference to underwater deepness and the elevation or heights above sea level including mountains: In the book Jim was reading he found out that bathyorographical data referred to pelagic or marine depths, as well as to the altitude of mountains.

The study and mapping of variations in the earth's surface, including depths of bodies of water and the mountains and the mountain ranges: In his geography seminar specifically dealing with bathyorography, Jude had to work on a map of an ocean and of a mountain of his choice.

1. Pertaining to the biogeographic realm of the ocean, or living in the depths of the ocean: The bathypelagic realm of the large open water areas of the world lies between the mesopalagic and the abyssopelagic layers at a deepness of roughly 1,000 to 4,000 meters (3,280 to 13,120 feet).
2. A reference to organisms living in the steep descent of the ocean bed from the abyssal zone to the continental shelf: Jack read about a scavenger that fed on the dead whales and squid in the midnight zone, or bathypelagic zone, of the sea where light does not penetrate.

A layer of the oceanic zone lying below the "mesopelagic" zone and above the "abyssopelagic" zone, at depths generally between 1,000 and 4,000 meters (3,280 to 13,120 feet): The bathypelagic zone receives no sunlight and water pressure is considerable. The abundance and diversity of marine life decreases with depth through the bathypelagic zone and the lower zones.

A living thing that thrives in the depths of the ocean: Bathyphiles are organisms that do well in the deep parts of the ocean which has a temperature of about 1 - 3°C.

An instrument for detecting photoluminescent signals in marine environments: A bathyphotometer integrates the system of using 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.

A leaf at the base of a stem functioning as an attachment to a substrate (layer): In his botany class at school, Tim learned that a bathyphyll was a leaf of a young undeveloped plant that looked different from the leaves that were produced later on when the plant was mature.

Planktonic organisms that undergo diurnal vertical migration, moving up towards the surface at dusk and down away from the surface at dawn: Bathyplankton live at a depth below the bathyal zone or in the greater depths of the abyssal zones.

A deep kind of breathing: Jane told her friend that she should practice bathypnea in order to deal with her issue of stress and as a good way to practice relaxation.

1. A self-propelled deep-sea diving submersible, consisting of a crew cabin similar to a bathysphere suspended below a float: A bathyscaphe is 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.

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.

2. 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".

An earthquake of deep origin recordable at seismographic stations around the world: In her book about earthquakes, Judy learned that a bathyseism was an earth tremor having its source deep in the earth and probably caused by tectonic action.