Denshi Jisho — Online Japanese dictionary

二階 にかい second floor; upstairs
Common word, Noun 
二階 にかいや two-story house
Noun 
二階 にかいや two storey house; two story house
Noun 
二階 にかいだて two-storied building
Noun 
二階建て にかいだて two-storied building
Common word, Noun 
二階建てバス にかいだてバス double-decker bus
Noun 
二階から目薬 にかいからめぐすり something that cannot be done no matter how hard one tries (and is slightly frustrating because of this)
Expression 

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