降海 こうかい Meanings Noun, する verb swimming downstream (to the sea) Kanji 降 descend. Read as コウ. 海 sea. Read as カイ. Words containing 降海 沈降海岸 (ちんこうかいがん) submerged shoreline 降海型 (こうかいがた) sea-run variety (of fish) Jinuma: Japanese Dictionary · Word lists