noun
hydrothermal vent
A fissure on the seafloor from which geothermally heated water issues. Used in geology, oceanography, and deep-sea biology contexts.
深海の熱水噴出孔の周りには、独特の生態系が広がっている。
Around deep-sea hydrothermal vents, unique ecosystems thrive.
Compound of 熱水 (ねっすい, 'hot water') + 噴出孔 (ふんしゅつこう, 'spout hole, vent'). The term is a direct calque of the English 'hydrothermal vent'.