Denshi Jisho — Online Japanese dictionary

一件 いっけん matter; item; case
Common word, Noun 
一件書類 いっけんしょるい all the papers (documents) relating to a case; dossier
Noun 
一件落着 いっけんらくちゃく an issue being settled; a case being closed
Noun, Suru verb 

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