underseas
Beneath the ocean
Underseas means beneath the surface of the sea, used as both adjective and adverb: underseas exploration, underseas cables, the vessel traveled underseas.
The word is interchangeable with undersea, though undersea is more common as an adjective and underseas slightly more natural as an adverb.
Self-propelled deep-diving craft
- sonarUnderwater detection by echoes
- divingEntering water deliberately
- expeditionOrganized exploratory journey
- researchSystematic fact-finding effort
seafloor · mapping · trench · hydrothermal · sediment · archaeology · geology · currents
Extremely deep, unmeasurable
- unfathomableBeyond comprehension or measurement
- hiddenKept out of sight
- unknownNot yet discovered
- depthsLowest or innermost regions
secrets · shadowy · obscure · enigmatic · veiled · lost · sunken · unexplored
Organism-generated light emission
- ecosystemInterconnected organisms and surroundings
- coralMarine skeletal formation
- planktonDrifting marine microlife
- marineRelating to the sea
biodiversity · habitat · benthic · pelagic · jellyfish · anglerfish · giant squid · tube worms
Propelled undersea explosive
- periscopeAngled optical viewing tube
- sonarUnderwater detection by echoes
- nuclearOf atomic energy
- diesel-electricCombustion-powered electric drive
ballast · depth charge · hydrophone · hull · propeller · conning tower · snorkel · crew
bathyscaphe
Self-propelled deep-diving craft
- sonarUnderwater detection by echoes
- divingEntering water deliberately
- expeditionOrganized exploratory journey
research · seafloor · mapping · trench · hydrothermal · sediment · archaeology · geology · currents · oceanography
abyssal
Extremely deep, unmeasurable
- unfathomableBeyond comprehension or measurement
- hiddenKept out of sight
- unknownNot yet discovered
depths · secrets · shadowy · obscure · enigmatic · veiled · lost · sunken · unexplored · murky
bioluminescence
Organism-generated light emission
- ecosystemInterconnected organisms and surroundings
- coralMarine skeletal formation
- planktonDrifting marine microlife
marine · biodiversity · habitat · benthic · pelagic · jellyfish · anglerfish · giant squid · tube worms · kelp
torpedo
Propelled undersea explosive
diesel-electric · ballast · depth charge · hydrophone · hull · propeller · conning tower · snorkel · crew · captain
underseasabove water
Not submerged, financially viable
surface · on the surface · overwater · terrestrial · land-based
underseasaerospace
Atmosphere plus outer void
atmospheric · aerial · terrestrial · overland · airborne