Denshi Jisho — Online Japanese dictionary

理解 りかい understanding; comprehension; appreciation; sympathy
Common word, Noun, Suru verb 
理解度 りかいど comprehension; understanding
Noun 
理解語彙 りかいごい passive vocabulary
Noun, Linguistic term 
理解力 りかいりょく (power of) understanding; comprehensive faculty
Noun 
理解不能 りかいふのう impossible to understand; impossible to decypher
Na-adjective 
理解し合う りかいしあう to reach mutual understanding; to understand each other
Godan verb with u ending 
理解を示す りかいをしめす to show understanding; to appreciate; to be positive about
Expression, Godan verb with su ending 
理解しがたい りかいしがたい hard to understand; Byzantine fashion
Expression 
理解を深める りかいをふかめる to cultivate a better understanding
Expression, Ichidan verb 

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