Denshi Jisho — Online Japanese dictionary

真剣 しんけん 1: seriousness; earnestness;
2: real sword (as opposed to unsharpened or wooden practice weapon) (practise)
Common word, Noun, Na-adjective 
真剣勝負 しんけんしょうぶ fighting with real swords; game played in real earnest
Noun, No-adjective 

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