Denshi Jisho — Online Japanese dictionary

最善 さいぜん the very best
Common word, Noun 
最善の策 さいぜんのさく the best policy (measure)
Noun 
最善の措置 さいぜんのそち best practices
Expression 
最善を尽くす さいぜんをつくす to do one's best; to do something to the best of one's ability
Expression, Godan verb with su ending 

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