Denshi Jisho — Online Japanese dictionary

重大 じゅうだい serious; important; significant; grave; weighty
Common word, Na-adjective, Noun 
重大 じゅうだいか aggravation
Noun, Suru verb 
重大 じゅうだいし taking (something) seriously
Noun, Suru verb 
重大 じゅうだいせい importance; seriousness
Noun 
重大犯罪 じゅうだいはんざい serious crime; felony
Noun 
重大問題 じゅうだいもんだい serious (vital) question; a grave issue; a matter of grave concern
Noun 

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