Denshi Jisho — Online Japanese dictionary

ぬま swamp; bog; pond; lake
Common word, Noun, Noun suffix 
こしょう lakes and marshes
Common word, Noun 
どろぬま bog; marsh
Common word, Noun 
ちしょう 1: ponds and swamps;
2: (Slang) (Derogatory) mentally-handicapped person
Noun 

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