Denshi Jisho — Online Japanese dictionary

かい 1: (biological) kingdom;
2: erathem (rock layer corresponding to the era in which it was deposited);
3: partition of land;
4: (Suffix) the world of (some category)
Noun 
さかい 1: border; boundary;
2: area; region; spot; space; environment;
3: psychological state; mental state
Noun 
かいめん interface
Noun, No-adjective 
かいらい frontal thunderstorm
Noun 
かいわい neighborhood; neighbourhood
Noun 
かいひょう boundary mark (on land or water)
Noun 
磁極 かいじきょく field pole
Noun 
磁石 かいじしゃく field magnet
Noun 
磁巻線 かいじまきせん field winding
Noun 
面化学 かいめんかがく surface chemistry
Noun 
面活性 かいめんかっせい surface active
Noun, No-adjective 
面現象 かいめんげんしょう interfacial phenomenon; surface phenomenon
Noun 
面張力 かいめんちょうりょく interfacial tension
Noun 
面活性剤 かいめんかっせいざい surfactant
Noun 

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