Denshi Jisho — Online Japanese dictionary

迅速 じんそく quick; fast; rapid; swift; prompt; streamlined; expedited; expeditious
Common word, Na-adjective, Noun 
迅雷 じんらい thunderclap
Noun 
奮迅 ふんじん impetuous dash forward
Noun 
獅子奮迅 ししふんじん being irresistible; being furiously vigorous; being intensely forceful
Noun, No-adjective, Adverbial noun, Suru verb 
迅速果敢 じんそくかかん quick and decisive; fast and daring; swift and resolute
Noun, Na-adjective 
迅速果断 じんそくかだん quick and decisive; fast and daring
Noun, Na-adjective 
疾風迅雷 しっぷうじんらい with lightning speed
Noun 
無常迅速 むじょうじんそく the (fast) pace at which life passes, and thus the nearness of death; promptitude of the changes of the times
Noun 
獅子奮迅の勢い ししふんじんのいきおい irresistible force
Noun 

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