Denshi Jisho — Online Japanese dictionary

海辺 うみべ beach; seashore
Common word, Noun, No-adjective 
海路 かいろ sea route
Common word, Temporal noun 
海馬 あしか eared seal (esp. the California sea lion, Zalophus californianus); sea lion
Noun, No-adjective, Usually written using kana alone 
海驢 あしか eared seal (esp. the California sea lion, Zalophus californianus); sea lion
Noun, No-adjective, Usually written using kana alone 
海鰻 あなご garden eel; conger eel (esp. the common Japanese conger, Conger myriaster)
Out-dated kanji, Noun 
海女 あまめ woman shell diver
Out-dated or obsolete kana, Noun 
海参 いりこ dried sea slug
Noun 
海豚 いるか dolphin (or other small toothed whales, such as porpoises, belugas, etc.)
Gikun (meaning) reading, Noun, Usually written using kana alone 
海路 うなじ sea route
Temporal noun 
海鵜 うみう Japanese cormorant (Phalacrocorax capillatus); Temminck's cormorant
Noun, Usually written using kana alone 
海路 うみじ sea route
Temporal noun 
海手 うみて place by the sea
Noun, No-adjective 
海邊 うみべ beach; seashore
Out-dated kanji, Noun, No-adjective 
海芋 かいう calla; Zantedcschia aethiopica
Noun 
海気 かいき 1: sea air; sea breeze;
2: ocean and atmosphere;
3: type of thin thread; textile type
Noun 
海黄 かいき type of thin thread; textile type
Noun 
海区 かいく ocean sector
Noun 
海砂 かいさ sea sand (sand collected from the ocean floor, as opposed to that which is used as an ingredient in concrete)
Noun 
海士 かいし seaman
Noun 
海事 かいじ maritime affairs
Noun, No-adjective 
海自 かいじ Maritime Self-Defense Force
Noun, Abbreviation 
海図 かいず sea chart
Noun 
海鼠 かいそ sea cucumber (Holothuroidea spp.)
Noun, Usually written using kana alone 
海馬 かいば 1: sea horse;
2: hippocampus;
3: walrus
Noun 
海保 かいほ Japan Coast Guard; JCG
Noun, Abbreviation 
海浦 かいほ seaside
Noun 

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