Usage patterns 重じゅう 大だい な 〈 事こと 〉 a serious/grave matter (e.g. incident, problem)
A serious accident occurred at the factory.
〈 事こと 〉 に 重じゅう 大だい な 影えい 響きょう を 与あた える to have a serious/significant effect on something
This decision will likely have a significant impact on future plans.
重じゅう 大だい な 責せき 任にん を 負お う to bear a heavy/serious responsibility
As president, he bears a heavy responsibility.
重じゅう 大だい な 決けつ 断だん を 下くだ す to make a serious/momentous decision
He made a momentous decision that would determine the company's future.
Kanji 重 heavy, important, esteem Related words· 6 重要 stresses general importance or necessity, while 重大 emphasizes the gravity or serious consequences of a matter.
深刻 highlights how severe or worrying a situation is, whereas 重大 focuses on the weight or significance of the matter itself.
大事 is a softer, everyday word for something important or serious, while 重大 is more formal and often used for grave, high-stakes matters.
重大 is a native Japanese word for 'serious/grave' importance, while クリティカル is a loanword often used in technical or business contexts with the same sense.
Show 2 more Show fewer 重大 is a な -adjective meaning 'serious' or 'important' for events and problems, while 重い can additionally describe physical weight.
重大 means serious or grave in a general sense, while 致命的 specifically implies that the seriousness leads to death or irreversible ruin.
Don't confuse with 重体 refers specifically to a patient's critical medical condition, while 重大 is a general adjective meaning serious or grave and is not limited to health.
重大 stresses seriousness or gravity (a grave matter), while 重要 simply stresses importance or priority; learners often confuse the two due to the shared 重 kanji.
Word family very serious matter; momentous event
aggravation; becoming serious; escalation
importance; seriousness; gravity
taking seriously; regarding as important
serious problem; grave issue; matter of grave concern
serious crime; felony
Etymology Compound of 重 (heavy, weighty) and 大 (big, great). The combination conveys the idea of something being weighty and large in importance or consequence.
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