noun
submarine volcano
A volcano located on the seafloor; synonymous with 海底火山 (かいていかざん).
See also: 海底火山
この海域には多くの海中火山が存在する。
Many submarine volcanoes exist in this sea area.
Synonym; both mean 'submarine volcano'. 海中火山 emphasizes being in the sea, while 海底火山 emphasizes the seabed.
Compound of 海中 (かいちゅう, 'in the sea') and 火山 (かざん, 'volcano').