Denshi Jisho — Online Japanese dictionary

こう pit (esp. of a mine)
Noun, Noun suffix 
はいこう abandoned mine; disused mine
Common word, Noun, Suru verb 
おうこう adit
Irregular kana usage, Noun 
かいこう opening of mine
Noun, Suru verb 
きんこう gold mine
Noun 
ぎんこう silver mine; ore
Noun 
こうこう shaft; mine; pit
Noun 
しゃこう inclined shaft
Noun 
たてこう shaft (e.g. in a mine); pit
Noun 
たてこう shaft (e.g. in a mine); pit
Noun 
たてこう shaft (e.g. in a mine); pit
Noun 
たんこう coal mine; coal pit
Noun 
よここう adit
Noun 
立て たてこう shaft (e.g. in a mine); pit
Noun 
にゅうこう entrance into drift or pit
Noun, Suru verb 

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